Apr 16, 2024     Installed rudder - (7 hours)       Category: Empennage

What we have here is a chicken and egg scenario. The rudder has been ready to install and rig since I got the fiberglass tips finished a couple of weeks ago. I thought it would be a quick project to knock out, but of course it never goes that way.

I had decided to route the wiring for the tail strobe per Vans OP-56 drawing, which has you rivet a wire tie mount to the fwd face of the rudder spar at a hole that already exists in the doubler for the lower heim joint. Unfortunately theres quite a thick material stackup there and the print calls for an LP4-5 rivet there. OP-56 is a generic print for all Vans models, so I guess that makes sense, but guess how many LP4-5 rivets are require for an RV-7?...hob about a big fat zero.

In the picture below, you can see where the mount is riveted through a hole in the doubler. there is a matching hole on the other side of the heim joint that doesn't go all the way through. I questioned this when I was putting the rudder together and Vans tech support told me that doubler is used in lots of different models and those two holes are predrilled for the RV-14. They told me I could match drill teh spar and and rivet them or just ignore them on the RV-7, so I chose to ignore them. Fast fwd a couple of years, and now OP-56 tells me that I can use that same hole for this wire tie mount. Handy! All this is to explain why there's an empty rivet hole on one side of this doubler in the picture, but I digress.

Anyway, right before we left for family vacation and sun n fun I ordered a few rivets from Vans.

Once I had the proper rivet installed I hung the rudder with the appropriate hardware, then routed and secured the wire to the tail strobe. I thought I'd be smart and install the lower rudder cap after that, but it turns out there isn't enough room to put it in place with the rudder installed because the tailwheel spring is in the way. So I pulled the lower two hinge bolts back out and was able to swing the rudder out enough to slip the lower fairing cap on, then secure everything again.

I torqued the fasteners via a Crowfoot and some careful positioning, and then riveted on the upper and lower cap fairings.

Note- I see a lot of people install the lower fairing with nutplates so they can get it off to work on the wiring to the tail light and I can't for the life of me understand why this is a thing. I just shielded the wire with some abrasion sleeve and left enough service loop that I can unscrew it from the rudder and pull it aft enough to unplug the spade connectors, then cut the wire tie at the mount that was installed a coupe of paragraphs up in this entry, then you can pull the wire out fwd and remove the rudder just like any other rudder. eeze peeze.

I've also seen people take all sorts of time and effort to make sure the rudder and V/S upper caps match perfectly by adding micro or body filler to one or the other. While I understand the sentiment, I don't think I'm going to do that. The curvature has an ever so slight mis-match between the two, but aerodynamically its insignificant, and I don't think it's worth the weight penalty of adding filler back there to try to get it show plane perfect.

At this point I also drilled a drain hole at the lowest part of the fairing also water doesn't get trapped in there. It's a 1/4" hole which seems huge, but it's per print taht it's supposed to be that size.

The last think I did was to run the magnetometer interference test again. I had done it when I installed the magnetometer, but there was lots of stuff not installed/functional at that time, including the tail strobe. Now that teh airplane is put together and is functional, it seemed like I should probably put it through its paces.

This test is somewhat lengthy. It suggests you runs pretty much everything through its paces; Box the controls, run the trim, strobes on and off, basically every combination and configuration you can imagine. I'm happy to report that it passed, with a high of only 17% of the interference limit reached in one configuration (Strobe on, elevator full up, trim servo running).

  Apr 03, 2024     rudder fairings - (12 hours)       Category: Empennage

Due to acquiring a used empennage with the wings I bought, most of which I replaced, I ended up with the old white fairings and also new gray ones. As I mentioned before, the white ones are lighter, so even though they're a bit thinner and seem a little less robust, thats what I elected to use.

The exception is the upper rudder fairing. The white one was about 1/2" shorter than the gray one and I was going to have to build it up significantly, so I used the new one up top on the rudder.

The bottom fairing has a molded in light cove, but there isn't room inside for the threaded plate that came with the nav light. Vans has you fabricate a mounting base out of 1/8" aluminum, tap threads into it, and pop rivet it externally to the light has something to screw into. Pardon me, but how much more hillbilly can you get?

I played with this for 2 days including research before coming across a solution somebody else had successfully with. Basically, lay up 2 piano hinge eyelets in flox inside the socket, then drill them and tap for #4-40 screws. That worked great and nothing cobbled together on the outside. I weighed it after and the whole thing including the light is still 2 oz lighter than the gray one just by itself. Success!

I'm following the Vans drawing for routing wiring to that tail light, and it requires a CS4-5 pop rivet to secure a wire tie mount to the fwd face of the rudder spar, but there are exactly zero of those in an RV7 kit, so I had to order a few. I won't permanently install the fairings until thats done.

I also took some time to get the gap right between the V/S upper tip and the rudder counterbalance horn. Vans doesn't specify a specific gap for this area, but on the elevators it's 1/8" so thats what I was shooting for here as well. I had the closeout on the aft face of the V/S cap a bit proud, an that opening wasn't quite big enough, so I block sanded it down and once it was right, I repainted it with dupli-color rattle can primer just to protect it from uv for now.

The side profile doesn't quite match. I haven't decided if I'm going to try to fill that with micro, or just let the paint shop deal with it.

  Mar 24, 2024     riveted on h/s tips - (.5 hour)       Category: Empennage

Just had a couple of hours in the hangar today, so I knocked out the simple task of riveting the fiberglass tips on the horizontal stab.

I questioned the build instructions here, because they don't call for any kind of doubler, just pull rivets right through the fiberglass. When I asked date question on VAF, I got the usual variety of opinions, but Scott McDaniels, who is a DAR and retired from Vans Prototype shop a couple of years ago responded that all the prototypes are built per print there and it's not a mistake, so I went with that and just riveted them on so that the bulb of the pulled end is pulled right up against nothing but fiberglass.

In spite of my best efforts, the gap between the tip fairing and the elevator counterweight ended up the tiniest bit asymmetrical. It's not much, maybe 1/16" or so, and it's only noticeable if you sight straight down between the two with the elevators neutral, so it's not worth fixing, but it's a little annoying. On the plus side, from every other angle they two fairings blend symmetrically and look very nice.

It's pretty exciting to see stuff like tis all coming together.

  Mar 23, 2024     Installed/rigged elevators - (16 hours)       Category: Empennage

16 hours for this? what the heck?!? But yeah, including troubleshooting, research and a side project for my hangar neighbor.

This week I tried to arrange my workflow so I'd always have something to do while waiting for epoxy to dry. So there was lots of stuff done in little chunks over several days, which is never the most efficient way for me to do something.

Anyway, I got the elevator tip/counterweight fairings done early in the week and kept coming back to this as the same time I was working on the rest of the fairings.

I started by permanently installing the trim servo in the l/h elevator. The wiring coming off of that is only a few inches long, so the builder is faced with a choice here;

Option 1 is to install a connector here from ships wiring. That has a couple of downsides. in order to remove/install the elevator, you would have to remove the servo which is not ideal for paint shop considerations. Plus in order to do that, you'd have to leave enough service loop in the wiring to actually get the servo out so you could reach the plug to disconnect it. This means you've got extra wire just flopping around in the elevator, crammed up in there with moving parts and adding weight in an elevator that's already close to being too tail heavy because of the servo and linkage in there, even with a full sized counterweight up front.

Option 2

Splice onto the servo wiring, extend the bundle under the empennage intersection fairing and add connector there, so that when you remove the elevator you don't have to remove the servo.

Ordinarily, I'm loath to splice a wire and then just add a connector a couple of feet away, but in this case it makes sense, especially since I know this has to come back apart right after phase one for paint, so I went with option 2.

I spliced a length of 5 conductor trim wire onto the servo by means of d-sub pins covered in heat shrink. Environmental butt splices would have been my first choice back here but even though raychem says that their red ones are good down to 26 gauge wire, I've never had good luck getting them to crimp tight enough. there just isn't enough conductor for them to squeeze down on unless you fold it back on itself. plus they're pretty bulky and heavy for this application.

Also, by using d-subs back here if the servo ever goes bad, I have the option of feeding the wire back into the elevator far enough that I can get the servo out and un-pin it back there without taking the elevator off, I have a lot of faith in d-sub pins when it comes to crimping stuff on wire this tiny and consider this is a "semi-permanent" splice.

I covered my new wire with snakeskin chafe protection, fed it out of the elevator and taped it out of the way while I was installing and rigging the elevators.

I had previously adjusted the elevator heim joints and had everything rigged properly in the garage. The r/h elevator was still dead nuts on. It swung freely and when you let go it flopped nose down as expected. The l/h one, even though all the rig pins went in and it swung okay, seemed a little stiff. I could easily move it with light fingertip pressure, but once I stopped, it stopped. It didn't continue on to its nose down position as I would have expected. I added a couple of washers under the nut on the inboard lead counterweight attach screw to ensure the mass balance is indeed nose heavy and also did some experimenting with removing different rig pins which revealed that the inboard heim joint needed another 1/2 turn to get it truly in line so that the elevator moves through it's whole range. i.e. light fingertip pressure to get it going, almost no friction, and a natural tendency to swing nose down.

note- in the final configuration, they are supposed to be statically balanced. i.e. when not attached to anything, including each other, they should hang level, not nose heavy or tail heavy. However, a bit of nose heavy isn't really going to hurt anything other than aerodynamic efficiency. In fact the build manual tells you to leave them a bit nose heavy until paint because paint will add weight aft of the balance point, then achieve static balance by drilling holes in the lead to balance them afterward. What you want to avoid at all costs is having them tail heavy, which can lead to aerodynamic flutter and catastrophic structural failure in flight. This is the reason for the big lead counterweights in the first place.

Anyway, the l/h one was good, then it wasn't. I can surmise that the reason for this was when I did SB-00036 REV 3, it has you add a doubler to the aft face of the aft h/s spar and replace the steel hinge parts with new ones that are dimensioned with the holes relocated the thickness of the doubler, which without looking it up, I seem to remember being .060". Vans machining precision is good, but it's easy to see how something could have gotten off by a teeny amount with changing all that out. Especially when you consider that the 1/2 turn adjustment that was required to bring it all back in line equated to a difference of only about .020". Certainly not enough to precisely identify with the naked eye when sighting down a row of 3/16" holes.

Later during rigging, I noted that the required washer stackup at the center bearing changed as well by the thickness of I believe one washer. I took pictures and included them below for future reference, but what I ended up with in addition to the big washer next to the bearing was two regular washers on the left and a regular washer and thin washer on the right

Once I was sure everything was set correctly, I pulled the elevators back off, torqued down the heim joint jamb nuts to 80 "/lbs with a crows foot, and reinstalled with appropriate hardware.

I noted that with the AN3-7A bolts called out, there was barely 1 thread showing past the lock nut. While this is the minimum allowable for a fiber lock nut, it seemed kind of odd, so I investigated more closely. Normally, an AN bolt is supposed to have the non threaded shank just barely protruding through whatever you're bolting up, and you take upon that space with washer. In this case, The -7 bolt was just about 1 thread too short.

No problem. I'll replace with a -8 bolt....Wait, why can't I find any AN3-8A bolts in my stash? I check online and don't see any at Spruce either.

The next day, I swing by work and mention that Spruce doesn't have these and when Airparts opens I'm going to give them a call and see if they have them. Out of curiosity we look in the crib which has every piece of hardware in the universe. Turns out we stock up to -7A, then skip to -10A, just like Spruce. Shop Manager/IA is now curious as well. He gets into the company internal parts tracking system. Turns out that out of all of Cessna/Beechcraft/Hawker/Textron Aviation, the only place AN3-8A bolts are used is in a now defunct Hawker product that was designed back when the Brits owned Hawker. The listed supplier is Textron Specialty Fasteners. There is a lead time and they cost about $20 a pop.

Second IA is hanging out so he starts looking online out of curiosity and discovers the almost complete non-existence of AN3-8A bolts. At this point, including me there are now 5 A&P's in the room, 2 of them IA's, and none of us realized that we've evidently never seen or used that particular bolt for anything.

So, the options are to either to go up to a AN3-10A and start stacking up washers, or do what Vans obviously intended and what 12,000 other RV builders have evidently done, and just use the hardware called out on the print.

Armed with this knowledge, I went back to the AN3-7A that's called out. I did use a thin washer here just to give myself an extra thread through the lock nut.

With that resolved, I rigged everything up and confirmed elevator travel with a digital inclinometer. The average numbers I got from taking repeated readings at different points span wise was 27 up and 25 down. This falls within spec.

I then returned to the trim installation. I installed a d-sub connector on the aft deck to join the ships side wiring to the trim servo. Followed up by routing/securing so that there was a good service loop on both sides as well as free wire to allow for elevator movement while still insuring that there was zero chance for anything to come loose and get tangled in the flight control rigging. A jammed flight control is my own personal phobia and I've taken great care on this airplane top make sure there isn't even a remote possibility of something coming loose and getting tangled up.

In order to do this, I needed to add a couple of wire tie mounts. The adhesive backing on these is just 3M double stick tape and while it sticks great, sooner of later it always fails, so I typically scrape that stuff off and glue them on with E6000 or something. In this case, the front one is glued on with RTV, with a healthy smear front and back to give the bundle some chafe protection against the spar. The aft one that you can see on the aft deck just in front of the aft h/s spar is somewhat critical in that if it comes loose, the wire bundle would be free enough back there that elevator movement could cause it to rub on stuff. With that in mind, I installed it to the aft deck with a pop rivet. It ain't going anywhere and now I have full elevator range of motion with no chance of anything rubbing, a nice gentle radius for the wire bundle to flex through.

With that done, I wanted to ops check the trim, and while it worked as expected with the hat switch, I couldn't remember how to get the indicator to show up on the G3X. I spent the next hour on VAF and the Garmin manual trying to figure it out before I almost accidentally stumbled on the correct field to touch to get into the calibration menu and set that up. In the end, all is well.

Since everything is effectively done back there, I decided to install the empennage intersection faring. I was just finishing that up when my hangar neighbor Ron Hart popped in looking for some help weighing his RV6A. He had just finished installing a full Dynon panel and needed a new W&B to wrap up his condition inspection.

I don't know that I've done a full weight and balance since A&P school, but it was a fun side project that took about 90 minutes or so and refreshed my memory about how that actually gets done, plus I got to hang out and talk airplanes with a new friend. Met his wife and also the A&P who's signing off his Condition inspection, who invited me to use his aircraft jacks when it comes time to get my plane back up in the air to align the gear leg farings, Bonus!

  Mar 23, 2024     and even more empennage fairings - (20 hours)       Category: Empennage

Fiberglass requires a different kind of workday structure. You have to be willing to spend hours and hours prepping, masking, applying, and waiting for the stuff to dry, only to sand 90% of it off and then go back with round 2 and 3 to fill in mistakes, low spots, whatever.

So tis week has had a lot of that. In the down time waiting for stuff to cure I occupied myself with various small tasks like working on instrument panel placard templates, dimpling holes in the empennage, rigging elevators, stuff like that.

I'll do a different entry for those things, but thats why you may notice 2 or 3 different entries all on the same date. There really wasn't much value in posting something that just says "sanded for two hours today"

In some of the pictures below, the fiberglass is obviously not finished to a showroom quality paint job. The intent here is to have it structurally sound and aerodynamically smooth, with scratches and pinholes taken care of and a coat of cheap primer applied to protect it from u.v. and other random environmental stuff while I'm in flight test. Thats why you'll see obvious tape edge lines in the primer on the elevator counterbalance tips, for example.

Anyway, over the past week in the fiberglass efforts I finished the empennage tips. You may recall from a previous entry that I had used foam plugs as part of the process. On the h/s tips, once I disolved the foam out I had to fillet some flox into the back side to give the structural bond some depth. By the time I did the v/s tip, I had realized that I could cut that fillet space into the foam plug and just fill it in from the front as part of the initial layup. This eliminates a step and saves quite a bit of time so I'm detailing it here in case anyone stumbles across this in the future.

I also finished the empennage intersection fairing to an airworthy state. What I mean by that is that finished adding back in the 1/2"-3/4" that I had mistakenly cut to short along the front edge (don't cut to the scribe line!), sanded it all smooth, and applied a coat of hi build primer to protect it from u.v. It's fitting pretty well and I'll fly it that way and then let the painter do his thing to make it perfect.

While in fiberglass mode, I also attacked something that's been bothering me for a while. I've seen lots of flying RV's where the trailing edge of the wingtip extends about 1/4" or so aft of the trailing edge of the aileron. Fine from an aerodynamic standpoint, but I just find it annoying that you work so hard on something and it visually just doesn't line up.

The obvious fix for this is to fly it, make sure you don't have to squash an aileron to account for a heavy wing, and then once the ailerons are 100% for sure where they're supposed to be, mark the tips with a straight edge and trim them to match the rest of the wing trailing edge.

The problem with this plan is that where the top and bottom of the wingtips meet at the trailing edge, it's a very acute angle. Vans has dealt with this by building up a structural fillet in there thats presumably flox or something, which is only about 3/8" front to back. If you cut off a bit of the trailing edge, you're going to cut into that structural bond, reduce it's footprint to the top and bottom surface, etc.

I thought about is for a while, and debated whether to just live with it as so many others have, but ultimately decided it was probably worth the effort to at least give myself the option of fixing it before paint without having to take a bunch of stuff apart.

Not a lot of pictures of the process, but I removed the wingtips, which were just clecoed on, cleaned out the trailing edge joint plus scuffed it up to give new epoxy something to adhere to. Because ether angle is so acute, access is limited and there were lots of sandpaper on a ruler/scotchbrite on a coat hangar wire in a drill motor/acetone rag on a stick type operations.

Once prep was done, I stood them up vertically with the trailing edge down, taped off the open inboard end, and poured the trailing edge full of a layer of epoxy/flox about 1/2" deep. I then topped it off with a ply or two of strategically placed 8oz cloth which adds ears that bond to the inner upper and lower tip surfaces in areas where I was able to reach with more conventional prep methods, so I'm 100% confident that if the bond between new epoxy and 17 year old wingtips ever breaks loose down in the pointy tip, the whole thing is bonded in at least a couple of places over a wider surface area and is physically too big to slide inboard and interfere with the ailerons.

This now gives me the option of cutting down these trailing edges to match the ailerons while still having lots of structural element in the trailing edge.

I have found that a big part of fiberglass efficiency is planning your work flow into a logical sequence. One of my wingtips had been banged into something before I bough it and had a chunk broken off the corner, so I did the inside of that one first, then the next day I cleaned up the broken corner, drilled a couple of #30 holed through it into the new epoxy on the inside, then when I was applying flox to the inside of the second wingtip, I was able to use the dregs from that batch to build back up the damaged area on the outside of this tip with a flox mixture that penetrated all the way through into the new stuff thats as laid up the day before.

  Mar 16, 2024     continued empennage fairings - (10 hours)       Category: Empennage

Pulled the HS tips off and sanded them more of less flat with a 1/4 sheet vibrating sander with 60 grit. Then trial fit everything back together with clecoes and measured to make sure I was in the ballpark of the specified 1/8" gap between teh elevator counterweight horns and the h/s tips.

Once I was happy with everything, I sanded the hardened flox to about 1/32-1/16 below the surface and them filled it back in with a skim coat of micro epoxy. Tip- Flox is harder than nails. If you try to hand sand that stuff it will take all day. since in this case I just needed it to be slightly concave, but not really precise, I sanded it down with a small flapper disk on a dremmel tool.

It seems like I could combine a coupe of steps here, so when I did teh V/S tip I did it a bit differently. I formed teh plug with a built in chamfer for flox so that if everything when were it was supposed to with no voids I wont need second step of additional plies on the inside once I melt the foam out.

Because of the shape of the foam plug, I was able to lay bead of flox about 3/8" deep recessed from the face. I them imbedded 4-5 plied of scrap glass I the flox on the face of the foam plus, taking care to ensure it was imbedded in the fillets/beads at the perimeter. The glass was literally just what I had laying in my scrap box and varied from 4oz to 10 oz. Because of the way I'm making this, they are just flat plies so literally anything would have worked here.

After that, I skimmed in a top layer of micro and set it aside to dry along with the h/s tips.

The elevator balance weight closeouts appeared that they were going o work, So I went ahead and riveted the tips to the elevators. The holes for this are pre drilled in the elevator skins and you just have to match drill the fiberglass. which I has already done, but I discovered that the two aft rivets are so close together taht after you get they first one in, teh tail prevents you from getting tiger opposite one inserted far enough to pull it.

Fortunately teh CS4 rivets that are called out have a huge grip range. I reasoned that they were actually longer than needed for the grip thats required in this application, and a bit of testing and experimentation proved that to be true. I was able to know the mandrel out of one shorten it about 1/16" on the 3M wheel, then reinstall the mandrel. That made it short enough to mostly seat in the hole. As I pulled it, I was able to seat it before it swelled enough to lock in the hole.

Once that was assured, I did a top coat of epoxy micro on those as well and will come back and sand this all at once. I spent some Tim after working on the rudder caps. The top cap is fitting pretty ell, but it's about 1/4" too short on the trailing edge. I know it would fly fine that way, but it's right at eye level when you walk around the airplane and it's just not aesthetically pleasing.

I think my choices are going to be building this up and making it longer, or maybe just going with the gray gelcoat tips in this one area because I know that it's a bit longer. Will think on this on Monday.

  Mar 13, 2024     empennage tip fairings - (11 hours)       Category: Empennage

I had the old but never used white fairings from the old empennage I got with my wings back in the day. These are 2007 vintage white gel coat instead of the gray ones that Vans currently ships, although they are the same part number.

They're quite a bit thinner layups than the gray ones, so a little less robust, but I weighed them on my postal scale this morning and discovered that cumulatively, they are a bit more than 7 oz lighter than the comparable ship set of gray ones. Save half a pound of the tail of the airplane? heck yeah! Thats the c.g. equivalent of deleting about 120 inch lbs off the aft c.g.

So after that revelation, I fit and started closing out the V.S. tips. I cut foam plugs, recessed them about .25" into the tips and filled in the recess with a couple of layers of fiberglass for a base and then slathered in an epoxy/flox mixture thickened with cabosil to make it peanut butter consistency. I protected the v.s. with waxed packing tape so I can get this apart again for finishing. Tomorrow I'll pop this out, and sand the plug flush. I'll then dissolve the foam with acetone and add a couple plies to the inside to make sure it stays put. One thing that would ruin your day real quick is if this came loose and jammed the elevators.

I then moved on to the the elevator tips. Task one was something I've been meaning to get to for a while, which was to install the trim motor in the left elevator. This seemed like a good day to knock this out so that the trim tab wasn't flopping around while I was manipulating the elevator while working on the fiberglass tip. No surprises here, other than it seemed like at full extension the pushrod might rub on the slot where it passes through the skin, so I lengthened the slot about 1/2" with a chainsaw file. There's a big doubler on the back side of this area so as long as you don't get into a rivet edge distance problem you have some liberty in this area.

The number 24 wires coming off the servo are too small to use most "normal" splices here, so I used high density d-sub pins covered in heat shrink and covered the wire in abrasion sleeve (snakeskin) These pins are only semi-permanent in that you can shave the heat shrink off of them and get it all apart again if the servo ever needs to be replaced, but the plan is to run the other end of that wire into the tailcone where it will connect to a normal d-sub connector. If the elevator ever needs to come off you can unplug it under the empennage fairing rather than having to remove the trim motor and fiddle with it down there.

One that was done, I started working on the tips. I trimmed and match drilled the white tip fairings then just eyeballed what made sense for closing out the forward end.

I shaved down the lead counterweights so that they were recessed all around what I envisioned the tip profile to be by about 1/16" on the front face and a bit more around the inner radius of the fiberglass. I did all this shaping with a coarse file and checked often to make sure I wasn't removing too much lead and that they were still nose heavy.

Once I was happy with everything, I prepped the inner face of the fiberglass tip by coarse sanding it to give the epoxy something to bite into, then mixed up some thick epoxy/flox and slathered a generous coat onto the sides of the lead counterweight and installed the fiberglass onto it so I have a thick buildup between the two.

I had already cut a couple of layers of cloth slightly larger than the face of the counterweight, so now I installed these as a wet layup and tucked the edges into the previously buttered edge gap with a popsicle stick and then finished off by covering the whole thing with more flox/epoxy.

The idea is that the entire tip including counterweight is now all bonded together. Once it dries, I can sand it down to final shape and have lots of thickness left due to my previous shaping of the counterweight.

once this is sanded to more or less final shape I may decide to cover the whole thing with another ply on the outside just for added insurance, but I don't see how it can go anywhere. If something cracks loose at some point in the far distant future it still can't go anywhere due to the squeeze out aft of counterweight.

It was a long day in the shop, yet somehow I neglected to take many pictures of the process. Hopefully this description might help somebody in the future.

  Mar 12, 2024     Empennage intersection fairings continued- & permanently installed VS & HS - (16 hours)       Category: Empennage

Over the last couple of days I've continued to plug away at this. Once I had the upper empennage faring fitting pretty well I moved on to the lower closeouts.

The way vans suggests you do these is to trim them to a 1/4" gap, then fill the gap with a piece of weatherstrip then tap the holes in the longerons and attach them with #6 screws. Way back during the initial empennage fit in the garage, I had blindly followed this process. When I trial fit them a few days ago I didn't like the way the weatherstrip fit and I certainly didn't like the way it looked. Just clunky. Because of the taildragger stance you can see it from anywhere in front of the airplane.

I went back to the print to refresh my memory and confirmed that there's a note which says you can skip the weatherstrip if you keep the gap to 1/32-1/16". I remade the closeouts out of scrap and spent quite a bit of time trimming the mating edge to conform to the lower skin of the H/S and they came out much better. I've got the bare minimum allowable gap here. At some point after flight test, I may lay bead of B2 in here to fill in the slight gap. That should be worth .01 knots of drag :)

I also elected to only tap two locations common to the aft inspection panel. I don't see why these should ever have to come off again, so I primed both mating faces and attached them with CS4 pop rivets. Quite a few people on VAF have done the same thing and have many years in service with no regrets.

On the aft lower corner of the upper fairing, you are supposed to drill out a rivet common to the fwd face of the aft double bulkhead and longeron and once again tap for a #6 machine screw. A thought on this; Standard practice says you don't cut fine threads in aluminum. because it's such a soft metal it's too easy to pull them out. I don't know why vans suggests this other than that it keeps the hardware callout simple.

I looked at this for a bit and after some careful measuring, determined that I had room to install a single leg nut plate through the skin just aft of the end of the longeron. I taped them in place and installed the rudder to make sure there was going to be room in there and that nothing would rub before I committed to drilling the holes.

The skin back there is only .025, but you have just (barely) enough thickness to countersink it for oops rivets to attach the nut plate without knife edging it, as you can see in the magnified picture of my test piece below.

This took longer than it should have, but I'm happy with how it turned out. The closeout strips are riveted on, there are only two tapped screws (at the top of the inspection panel) and the aft ends of the upper are secured where they won't be flopping around.

I installed nutplates for the upper empennage fairing, then permanently attached the vertical and horizontal with properly torqued hardware. Note- Looking at the forward H/S attach points with a mirror, it seemed like the bolts were a little long. I ended up adding a second washer to ensure The nut wasn't bottoming out on the shoulder of the bolt prior to achieving the correct torque.

I wrapped up the day by spending about about 4 hours today looking for the elevator and H/S fiberglass tips. I tossed the hangar twice, then drove home and looked all over the garage and basement, then back to the hangar in case I missed them. Gave up and cleaned the shop for a bit before coming home for the day, gave the garage one more look see and finally found them in a Tupperware tub that had gotten shoved behind a dog crate sometime in the last 2 years.

fitting of these will start tomorrow.

  Mar 04, 2024     worked on empennage fairing - (4 hours)       Category: Empennage

After laying this up a day or two ago I popped it off the airplane and laced into it with a sanding block. 4 hours later, teh leading edge is looking pretty good.

The sharpie line in the first picture represents the minimum trim line this is where I should have trimmed this to in the first place before I cut off too much.

In the second and third pictures, I laid out some reference lines to get the general shape symmetrical. You have a lot of leeway on the actual shape up here, but if it's not the same on both sides it would be really noticeable. I just used the two rolls of tape you can see in the background to make the radiuses.

It's not done yet, but as you can see in picture for, its coming together nicely.

  Mar 02, 2024     fairing work - (12 hours)       Category: Empennage

When I originally started fitting the empennage fairing I made the rookie mistake of trimming it to the scribe lines and it was about 3/16" too short on the leading edge. Everybody says that these fit horribly anyway, so when I ordered the intersection fairings from fairings etc I ordered their aftermarket empennage fairing as well.

Unfortunately, the fit on it isn't great either. It has significant gaps around both the vertical and the tailcone that I think can only be alleviated by splitting it down the middle and bringing the two halves closer together.

Since I'm going to have to do some fiberglass work anyway, I went back to the OEM fairing which is quite a bit smaller with tighter radiuses which I think look better, although this is just a personal preference.

I sanded a fillet to the leading edge and laid up an extension of fiberglass and flox. Once this dries, I'll pop it off the fuselage, sand it smooth and trim it to get back the 3/16 or so that I erroneously cut off. It's actually fitting pretty well everywhere else,

To finish this, I think I'll add a bit more of a wrap around where it meets the leading edge of the h/s and I may need a little filler to tighten up the gap around the fwd section of the vertical, but otherwise I think this is going to fit pretty well

  Dec 23, 2023     SB-00036 rev3 - (6 hours)       Category: Empennage

The Empennage has been done and on the shelf for a while now, and in that time, a new service bulletin was issued for the horizontal stab that addresses potential cracking of the aft spar at the outboard elevator hinge points.

This SB requires continual inspections for cracks and if you find them depending on severity you can install a doubler front and back or you may have to replace the spar.

If there are no cracks, you can eliminate the need for annual inspection, by preemptively installing the external doublers from the SB kit but in this case (no existing cracks) you don't need to add the internal ones.

The instructions call for drilling a 7/16" hole in the end rib, drilling the existing hinges and some skin rivets off, inspecting/sucking debris through the 7/16 hole, and reinstalling doublers and new steel hinge angles with Cherry rivets.

I know I don't have any cracks since this h/s has never been in service, so I elected to skip the 7/16 hole as well as the cherry max fix.

I drilled out enough skin rivets that I could get a tungsten bucking bar in there and after appropriate cleanup and deburring, shot the new parts on with conventional rivets, which is an alternate method of compliance. This h/s is brand new and unpainted, so it just made sense to me to do it this way and once I figured out how many rivets I needed to drill out it was probably just as fast and trying to built a ship in a bottle through a 7/16 hole and then mess around with lubricating Cherries and hoping I could get them to pull right with a hand puller.

This all went well, just a bit time consuming. The only thing I have left to do is ream out the center holes to take a hinge bolt. It's hard to get a picture but I sighted through the holes an they all line up. In one of the pictures below you can see that I shined a flashlight back toward the camera from the other end and you can sort of get the idea

  Jan 25, 2022     H/S tip fairings & Rudder lower fairing - (16 hours)       Category: Empennage

Holy Cow- It's been over a month since my last entry.

In the last month there was Christmas here in ICT, then in Missouri for a few days to see my mom and dad, then New Year, then I had to renew my CFII, then I had Covid. Yikes!

With all that going on, I really didn't have any big chunks of time to spend in the shop, but just a 1/2 hour here and there, which is absolutely the worst way for me to get anything done.

Having said that, I had a few hours yesterday and today, and was able to get the lower rudder fairing and the horizontal tip fairings trimmed and clecoed in place. The white fairings in the photos are old fiberglass that I inherited with the used empennage and wings that I bought, while the gray stuff is new from Vans. The finish is much smoother on the gray components, but It will all need some finish work eventually to make it fit right. I will likely leave everything in this configuration for a while and knock out all the fiberglass finish work at once.

Once that was done, I shifted gears and final drilled the slider track to the tailcone and temporarily attached with enough #6 screws hole it in place. I used the RV8 track which is longer, so that I can do the super tracks mod without having to make a 2 piece track. I haven't match drilled all the way to the aft end of the track yet because I'm not sure how much extra material I'll be able to cut off the aft end. I'll be able to do the final size/fit of this later after I do the rest of the super track install in a few days.

  Dec 17, 2021     more fairing work - (6 hours)       Category: Empennage

So I took another look at the H/S tip fairings and realized I had a problem. It seemed like I had plenty of room inside the ends of the H/S for the flanges on teh fairings, but on closer inspection, they were riding up on the flutes of the end ribs.

I got out the dremmel and scalloped the flanges to relieve them where there was interference, which is shown in one of the pictures below. Ultimately, I still wasn't happy with the idea of the fairing flange riding inside the flanges of the end ribs so I trimmed the entire fairing flange back for clearance.

That resulted in about 6/32 e.d. for a couple of the rivet holes in the fiberglass, so I may bond in a light aluminum backing strip around the rivet holes, especially since theres going to be the back side of a pop rivet. Haven't decided yet, because there isn't much meat there for pop rivets to hold onto, but then again, there's no real stress on them either and the leading edge gets epoxied in place so it's not like it can go anywhere.

Anyway, thats a decision for another day.

Decided to take a break from H/S work and started trimming the R-911 lower rudder cap. This proved to be more detailed than just trimming to the mold lines.

Because this is a tail dragger, the rudder cap needs to be high enough to clear the tailwheel spring, as seen on drawing 27. The mold lines have it sitting low enough that it flows as a continuation of the belly skin loft line, which would look cool on a 7A, but isn't going to work here.

I looked as several build logs to see how people have dealt with this. Found some where they had cut off the bottom of that fairing and reglassed it flatter, but that doesn't seem necessary in my case. Other guys have just positioned the whole thing higher by trimming more off it, and thats what I ultimately ended up doing.

At this point I've got a pretty decent fit, but it required trimming the t.e. as much as possible ( the position of the tail light is the limiting factor here) and the front end 3/8 more than where I was at originally. This leaves about 1/4 inch clearance with the tailwheel spring at the leading edge, and obviously a ton more as they diverge aft, which should be plenty.

Fiberglass requires a respirator and makes a huge mess, so I didn't get many pictures while I was trimming a little bit at a time until I got a decent fit. I'll continue this next time and try to get some better pictures of the finished product.

  Dec 15, 2021     elevator tips - (3 hours)       Category: Empennage

I final sized the holes for the rudder stops, then primed the mating surface of the tailcone skin and the rudder stops themselves. Set them aside to dry, and spent the rest of my shop time trimming and match drilling the right elevator tip.

I've started using my dotco with the cutoff disk Vans supplied for cutting the canopy. It works great for that and I figure since they sent two there's no reason not to use this one up on fiberglass since it's so much easier than a small cutoff wheel in a dremmel or a blade on a vibrasaw. After match drilling, I countersunk just using a dull 3 flute countersink in my deburring handle so I wouldn't ruin one of my good ones.


No real surprises here. Like the empennage fairing, it will require some tweaking during final fiberglass work, but at this point, I'm calling it good.

  Dec 15, 2021     ELT antenna - (2 hours)       Category: Empennage

I was out of town for most of last week and then was sick as a dog for the first part of this week, so I haven't worked on the project for a while. Decided to get back in the saddle with something easy, so I fabricated a mount for the ELT antenna.

This ELT is approved for two different antennas. I mistakenly ordered it from ACS with the longer of the two and didn't think that it would fit under the empennage fairing, so I ordered the shorter one from Dodson off a wrecked Bonanza. Turns out the longer one will fit as long as I take care to insulate and secure the tip so it doesn't rub against the aft H/S spar. My plan right now is to use the longer antenna as long as the magnetometer I'm planning to put back there passes the ops check, but it's nice to have options.

Anyway, the antenna mount is a simple piece of .032 bent into C channel for rigidity. It's clecoed on for now, but you can see in the picture how it crosses the starboard lightening hole in the F-709 bulkhead. and will just be held on by a couple of rivets in each end.

  Dec 06, 2021     empennage intersection fairing - (2 hours)       Category: Empennage

started working on the intersection fairing. at first glance, it doesn't look like this thing would ever come close to fitting, and guys have epic tails of how bad the fitment is on these fiberglass parts, but after trimming it back to the mould lines it stated looking pretty close.

It will eventually need a little flox and some creative extensions laid up where it wraps around teh H/S leading edge, but it's good enough for now so that I can locate nut plates and whatnot. I'll come back to later and do all the fiberglass finishing at once. Overall, I'm pretty happy with it at this point

  Sep 29, 2021     rudder fitting - (5 hours)       Category: Empennage

Finished the temporary installation of the elevators by installing the 2 stacks of washers that I super glued together last night. Was able to fish each side in as a unit with a pair of curved needle nose pliers. worked well, even though I couldn't see in there due to the vertical stab aft spar now being in the way.

While I was at it, I made a new hinge pin for the elevator trim. The one that comes in the elevator kit is just the right length to install, but doesn't give you any extra pin length to have anything to safety, so they tell you to do it later, which might as well be now while it' right in front of my face. Safetied it based on what's depicted on the drawing, but theres no dimensional callout, so you're just left making it look like the picture. I drilled a #50 hole centered on the flange and safetied with .032 wire.

I then got the rudder out of the basement and peeled the blue vinyl off. Back in the day I knew this was going to be laying around for a while and I didn't want the rivet lines to get all beat up, so I had taped over the rivet lines after riveting. Unfortunately, I had run out of blue 3M tape and finished up with a roll of masking tape I had handy. Turns out that was a big mistake.

The glue on that tape had turned to tacky mush, and scrubbing it off with acetone made it even stickier. I went through about 1/2 pint of acetone and a 1/2 roll of paper towels to get that goo off. Never again.

I thought when I built this I had lined up the Heim joints per print, but I remeasured because I couldn't 100% remember what I had done back then. They were off a little to what's suggested as a starting point in the build instructions so I reset them. I noticed later that here's a discrepancy in the dimensions between the print and what's recommended in the instructions. In my case the instructions turned out to be closer.

I eyeballed to the center of the holes and set to to the instructions and it was nearly perfect. After the first trial fitting on the V/S I ended up only having to adjust 1 joint by 1/2 turn to get all three to a point where 3/8" brass rig pins slide in. Bonus, the gap between the rudder balance horn and the top of the V/S was a constant 5/32 along it's entire length, i.e. everything is in alignment.

Unfortunately, I did run into a problem that took some experimentation to fix; When I tried to get the side to side swing called out in the instructions, The left side leading edge of the rudder was rubbing on the trailing edge skin of the V/S at about mid span vertically on the left side. Also, even though I left the rudder stops a little oversized due to people saying they're too short, turns out they were STILL too short.

Anyway, back to the rubbing issue; I tried unscrewing the heim joints to move the whole rudder aft and relieve the rubbing issue, but I was having to go out enough turns to get enough relief that I was pretty close to min. thread engagement on one of the joints - the center one if I recall correctly. It would have worked and would have been within spec, but I don't like being at the end of the adjustment range on anything if I don't have to, and now is the time to deal with it.

I eventually decided that since the v/s skin runs aft past the aft spar by about 1/2 inch I could file a bit off the trailing edge skin at the problem area and get clearance there without getting crazy with backing out hinge joints.

Took this in 3 or 4 bites, about 1/64th at a time. reinstalled the rudder after each one to get an idea of where I was at. Ended up taking off probably about 5/64" in the problem area.blending into a shallow transition over about 10" vertically, which makes it unnoticable. It gave me a constant 1/16 gap between the two skins at full deflection, even after I cranked all 3 heim joints in 1/2 turn from where I's started.

The instructions say that deflection is supposed to be 35* which is obtained with the stops set so that there's a 1 1/8" gap between the rudder skin and the aft corner of the elevators at full deflection. That sounds reasonable, but it's an awfully specific number for something that's essentially hand made.

Out of curiosity, I looked in the flight test portion of the manual and it says travel is actually max 35* min 30*. I was curious, so I dropped some plumb lines, drew lines on the floor and got out the protractor. According to my rough calculations, I'm set up for 33* each way which is right in the middle of where I want to be, Sweet! I still will need to remake bigger rudder stops, but otherwise I'm pretty happy with today's efforts.

  Sep 28, 2021     re-installed empennage for rigging etc. - (2 hours)       Category: Empennage

Not a lot of time to work on the plane today, but I was able to knock out a few things.

Riveted the fwd shim and attach angle to the fwd v/s spar. The first couple of pictures below show the shim upper edge flush with the flange that sticks down from the v/s nose rib. flange and rib are both .032 so it worked out okay to allow the attach angle to over lap the flange by about 1/16" Since everything is nice and flat, the only concern I can see here is would be if any of the rivets ended up too close together, but I measured before I started riveting and determined that I have plenty of pitch on them.

Re-installed the vertical stab, snugged down all bolts and was gratified to measure everything still plumb and true. I measured the aft upper corner of the V/S to the tips of the H/S and the measurements vary between "perfect" and off by about 1/64" depending on where exactly I hooked the end of the tape measure and which rivet or edge on the H/S I measured to. That's easily within the possible error of how I'm hooking the end of my tape measure against the tip of the tail so I'm pretty happy with that.

Re-installed the elevators with rig pins and then discovered that it's pretty much impossible to fish washers into the gap between the center bearing and the elevator control horns because you can't see or fit a pair of forceps in there due to the V/S aft spar now being in the way.

I know the stackup of washers required since I had this together before, so stacked them up on an old AN4 bolt to center them with each other then glued them together with a drop of superglue. I now have two "bushings" instead of 6 washers to deal with. I believe I can fish these two stacks into place with a pair of needle nose pliers but will come back to this tomorrow.

I also fabricated the F-789 pushrod. I had cut the tube to length and primed inside and out a few days ago, so all I had to do was smooth out the primer on the interior ends of the tube, insert the ends, drill with my drill press and a V block, and attach with 6 blind rivets on each end per print.

On VAF that lots of people have complained that this pushrod is almost impossible to install due to the second bulkhead behind the baggage compartment being in the way of sliding it straight in from the aft side. People have resorted to all sorts of stuff to get it where it belongs; bending it like a bow and hoping it springs back straight, making it shorter by not riveting on the ends until it's in place, etc. Turns out you don't have to do any of that stuff.

I can't take credit for this because I saw it in online somewhere, but I've captured the process below so hopefully it might help somebody else who's struggling with this on down the line;

Basically, instead of obsessing about getting it past the 2nd back bulkhead and getting a straight shot into the tunnel from the aft side, you start with the fwd end in the tunnel aft of the flap actuator assembly and with the rod on the right side of the F-728 vertical assembly. Then slide it forward until the aft end can be lowered into the tunnel, then slide it aft into position. Easy!

  Sep 27, 2021     Mounted Vertical Stabilizer - (12 hours)       Category: Empennage

Well, I've got to say that I was expecting this to be easier. This entry represents about 12 hours over 3 days

It's become my routine to peek at several build logs on line before jumping into a new section, in order to get more of an overview than I can sometimes see in the build instructions. Mostly when it came to the vertical stab people just said stuff like "uncle bob came over and helped with the vertical stab. don't cut too much off the front" In my case, it was a little more involved.

I spent way to long figuring out what was going on here and where the potential trouble spots are, so I'm going to attempt to document it in detail here in case it might help out anyone else down the line.

Clamping the vertical stab in place, you have 4 dimensions to account for;
1- height of the rear spar at the F-712 bulkhead
2- perpendicular to the H/S
3- rudder hinge line straight.
4- leading edge offset 1/4" for left turning tendencies

So, lets jump in;

The plans have you cut 5/8" off the fwd spar so it will nest nicely with the H/S at the fwd attach interface, but several people on VAF hav had issues and said that was too much, so I started by cutting off about 1/4" just to see what it looked like.

To cut to the chase, here are my observations; If you locate the aft spar properly, 5/8" is probably in the ball park, but I can see how jut a little error back there could really effect the front. Also, you move the front attach point up or down to adjust the hinge line on the aft spar, and between those two things, I can see how you could run out of spar stub real quick if you cut too much off and were required to move it in that direction.

Anyway, trial fit seemed okay, but the upper rudder hinge was about 1/8" too far aft. i.e. with the aft spar clamped in position, the front spar needs to be brought down in order to bring the upper hinge fwd and get all 3 in a common plane so the rudder will swing without binding. It can't come down any further because I only trimmed off 1/4" so, back to the bench and trim off another 1/4" I repeated this process until I had taken off approximately 5/8" or maybe even a little more.

I should also mention that the way Vans tells you to check this is with a straight edge at the aft edge of the hinge brackets on the v/s. The implication is that if the hinges line up, the holes in the hinges will line up.

Before betting the farm on that, I checked with a mic and sure enough, the holes vary in location by as much as .030 fore/aft. I didn't build the v/s, it came with the used wings I bought, so I don't know if they came from vans that way or if there was some variation in the way the previous guys cleaned the holes up. At any rate, a straight edge along the back of the brackets isn't going to give me a good result, so I did what many others before me have done and ran a tight string through the holes so I could check alignment.

Anyway, to circle back to what I said before, the top hinge was too far aft. In the build instructions, it says to adjust this the fwd spar stub can be positioned either side of the F-781 attach plate and that you can also shim as necessary. it says to position the spar aft and maybe add a shim to bring the top hinge aft.

For the longest time, I couldn't see how pushing the fwd spar aft at the bottom could bring the upper hinge fwd. it seems counter intuitive. I played with this for a long time trying to figure out what was happening here, and finally it became so obvious I felt stupid for not seeing it immediately; because the fwd spar and attach plate are canted at an angle to everything else, if the spar is aft of the attach plate, it's also lower. Ergo, you can raise or lower the fwd spar slightly just by which side of the plate you put it on.

That's really what this adjustment is about; raising or lowering the fwd spar stub, which brings the aft top corner of the v/s fwd or aft. The instructions also give you a dimension and material callout on drawing 27A for the shim, but no thickness callout, which indicates that it can be any thickness it needs to be, within reason, to get the job done.

Looking at it this way, the limiting factors on the length of the fwd spar stub then become a max of when it starts to interfere with supporting structure (too long), or when you run out of edge distance on the pre punched rivet holes on the F-781 attach plate (too short), depending on how you have to adjust it vertically to bring the hinges into alignment.

If you get need to move the top rudder hinge WAY fwd, it's also possible that you can run into trouble with the attach plate lapping up on top of the flange of the lower v/s ribs which stick down and are riveted to the fwd spar on both the fwd and aft sides. Lot's of stuff potentially going on here.

I didn't realize all this when I located the aft spar vertically per print, and while I got it as precise as I could, looking at it after the fact, it's ever so slightly lower than "perfect." You can see this in the picture below that shows the bolts installed through the hinge bracket if you know where to look. The sharpie marks should be aligned with the upper surface of the upper hinge bracket in that picture. It's lower but about he width of a sharpie line. This, combined with the variation in the hinge brackets, caused me to have to make many adjustments, trimming off a little bit of the fwd spar at a time until I got it where I wanted it. more on tis a couple of paragraphs down.

I didn't mark 5/8" from the end before I started trimming, so I don't know exactly how much I trimmed off, but I have a sneaking suspicion it was probably 1/6" or so more than the 5/8" callout. I think this because when everything was positioned correctly, the upper edge of the attach plate was lapped up on the flange sticking down from the nose rib at the spar by about that much.

Fortunately, I needed a .032 shim between the spar and the attach plate, which is also the thickness of that flange, so it can overlap slightly and everything still sits flush with solid edge distance on all the rivet holes both top and bottom on the attach plate. I feel like I dodged a bullet there, and I could have eliminated a bunch of this monkey motion by just scooching the aft spar upward by about 1/16" which would have made everything in the front a corresponding bit longer and likely eliminating the need for any shimming.

Once I had all this figured out, I clamped it with about a billion clamps, remeasured everything, and reamed the aft v/s spar to the evaluator up stop and put some bolts in there to hold everything in position. I then remeasured everything again, was feeling pretty good about myself, and then realized it all had to come apart again.

Now the real fun begins; on a taildragger, there are three bolts that go through the bottom of the aft spar, through the bulkheads, and through the aft flange of the tailwheel weldment, which of course, you can't see except with a mirror. Lots of opportunity to blow edge distance on one components or another. Took a bunch of measurements to identify location, then removed the v/s and pilot drilled #40 through the bulkhead into the weldment. The lower hole is centered on the tooling hole on the F-712 bulkhead, so that one was easy, but the upper 2 can blow out the e.d. on the tailwheel weldment on the fwd side or on the lower rudder hinge on the aft side if you're not careful.

Once pilot drilled, I measured everything inside with a small scale and inspection mirror to confirm good e.d. on the fwd side, then re-installed the v/s, this time with the washer on the left side between the spar and the up-stop per print to allow for the 1/4" offset at he leading edge, and match drilled #40 from the inside with a 90* drill. This allowed me to confirm good e.d. on everything on the aft side.

Now that everything was pilot drilled, it was a simple matter to bring the holes up to full size. Note- You have to pay attention here, because on print 27A (tricycle gear) there are 4 AN3 bolts here that go into the tail tie down structure. On print 27 (tailwheel, the 3 bolts are obviously a different location and configuration, but they are also a different size (AN4). Since I'm building a 7, they are AN4 bolts, so I upsized these holes by drilling them slightly under and then reaming them final size with a .249 reamer.

Once the aft side was done, I snugged down bolts in all the holes, verified the offset up front and once again measured everything, especially the rudder hinge line to make sure nothing had shifted. Then I upsized the bolt holes common to the F-781 attach plate and the HS-710 & HS-714 angles by drilling them up from #30 to slightly undersize and finishing them off with a 3/16" reamer. Snugged some bolts down in them, then FINALLY match drilled the fwd spar stub to the F-781 with my 90* drill and enough holes that I could get some clecoes in it and make sure everything is going to stay put.

Once again removed the v/s unclecoed the F-781 and shim and primed them.

Looking back on what I just wrote, I can see a bunch of wasted effort here, Now that I have an idea what the end result should be and what gotcha's need to be accounted for, I could have done a bunch of these steps in a slightly different order and saved myself about 1/2 of the put-together-take-apart-put-together operations. But, they payoff for all this is that tomorrow I'll rivet F-781 to the fwd spar stub and this thing should just drop together smooth like butter.

  Sep 22, 2021     rigged elevators - (8 hours)       Category: Empennage

Built F-790 aft elevator pushrod. I don't have a tubing cutter that will handle that 1.5" pipe, so I ended up having to carefully cut it with a hacksaw. I cut it to the exact length specified on the print, but wish I had bumped it up by about 3/8" or so. When assembled, the length turned out okay, i.e. when rigged each end had more that 1/2 of the threads engaged, but not a ton more. If a jamb nut gives it up and it the rod unscrews itself until it bottoms out in one direction I still have about 1/4" of threads engaged on the other, so there's no way they can unscrew themselves far enough for one to fall out, but if I had made the rod 3/8 longer, teh margin would have been more like 7/16."

Installed elevators with rig pins, stacked up the appropriate hardware at the center aft bearing per print. This requires several washers stacked up to fill in the gap between the control horns and the center bearing and I've got to say I'm not crazy about this arrangement. I may eventually try to have some steel tube machined to make spacers for this area for a cleaner installation.

The print tells you to deal with the extra gap at the pushrod to control horn bolt the same way, but also says alternately you can take up the gap by by making appropriate shims from AT6 tube stock. The stackup would take about 4 washers per side, which looks really cobbled together and hard to assemble without dropping washers everywhere, so I took the time to build spacers.

I cut them to .25" each and then turners then down by chucking them up in my drill press and bringing them down on a file to mill off the end. I continued the process with lots of trial fitting until I was happy with the fit. For future reference, each side ended up being about .230" which is a snug fit without prying the horns apart.

One more thing about rigging. The build instructions tell you that the way to rig this is to clamp the elevator balance horns so the elevators are in trail, then adjust the length of the F-790 pushrod until the F-635 elevator bellcrank is vertical. However, there there is no detail about how to determine vertical on this component other than to say that you can get it close (but not perfect) by slipping a socket through the hole in the supporting structure onto the lower bellcrank bolt.

I went to the VAF to see what others had done. That, combined with a close review of a bunch of different prints, determined that "Vertical" meant parallel to the F-728A channel.

After tinkering with this for a while, I determined that the easiest way to determine this was to put a bolt in the lower bellcrank hole and then just measure from the top and bottom bolts to the channel. In my case, this dimension is approx. 3 3/16" from the fwd side of each bolt to the fwd face of F-728A.

Had a little bit of time still available, so I cut the F-789 pushrod tube to length (making this one 1/8" longer than called out on the print) ran a green scotchbrite pad wetted with acetone through it a few times and also prepped the exterior, then primed it. I'll let the primer dry overnight and then finish this assembly tomorrow.

I also marked the F-781 vertical stabilizer attach plate and clamped it in position. Then I measured between rivets to determine the tailcone centerline and marked a reference in preparation for installing the vertical.

  Sep 21, 2021     Horizontal stab wrapped up - (7 hours)       Category: Empennage

I still hadn't heard back from Vans re- tooling holes in the wrong spot on H-00005 ribs on the h/s, so I called as soon as they opened up.

Talked to Kevin in Builder Support and he told me basically that all I needed to do was position it with the .125 shims under the front spar and the 3/16" spacers (drill bits) under the rear spar and drill it. He said I could also find the chord line of the h/s and measure from that. He went on to say that I could check for for twist with a digital level etc, which I has already done. Basically the objective is just to make sure the chord of the h/s is parallel to the longerons

Also, he mentioned that later on if I didn't like where the incidence was set, I could easily change it by changing the thickness of the fwd shims.

While I had him on the phone, I verified that it didn't matter what I made those shims out of, because yesterday I discovered I only had enough AB-4 bar scraps to make one side, so I had made the other one out of a chunk of AA-6 that I had in my scrap bin. He confirmed that the alloy material is completely irrelevant as long as it was the right thickness.

I told him to please delete my email from the day before, or check it as responded to or whatever, but later on Gary emailed me back anyway and said that the H-00005 had been redesigned since that instruction was written, and that the tooling hole location had changed, and to just put the shims in and don't worry about it.

In the meantime, I couldn't let well enough alone, so I had spent a couple of hours crawling around this thing measuring from about a dozen different points, including marking a center line on the ribs with a micrometer to find the chord so I could confirm parallel to the aft deck/longerons and measuring from the bottom of the lightening holes to the deck.

With all this measuring, I was able to confirm the angle of incidence, and to make sure that it was level side to size etc.

Ultimately, I made myself feel a lot better with all this monkey motion, but it didn't really accomplish anything else, because they were right, I didn't need to do anything other than make sure it was positioned correctly with respect to the shims and it was spot on.

Back drilled though the vertical bars and aft spar to #30. after each hole, I sucked it down with a draw cleco. Once that was done, I up drilled to #21 from the aft side, using a drill cup to make sure the holes were perpendicular.

After each hole was brought up to #21, I reamed it to final size with a piloted reamer from the aft side, and snugged down a bolt before moving on to the next one.

  Sep 20, 2021     h/s continued - (6 hours)       Category: Empennage

ran down to the yard store and picked up some appropriate size stubby bits for my 90* drill. Finished drilling the fwd h/s spar without issue.

Slid a couple of 3/16 drill bits under the aft spar to act as a spacer per instructions, but then I ran into a surprise. The build instructions then tell you to measure from the tooling holes on the inbd ribs to make sure the chord of the h/s is parallel to teh aft deck, i.e. 0* angle of incidence.

I just about have myself a heart attack when I tried that and discovered teh aft tooling holes on H-00005 were at least 3/16 lower than the fwd ones. Once I got over my panic, I looked at it closely and discovered taht hose holes aren't in the center of the web. There's no way that measuring from them will tell you anything.

Took pictures and sent to Vans for clarification, then applied a second coat of epoxy to the tailwheel hardware.

I also took the opportunity to finish priming the outside of the F-790 pushrod

  Sep 19, 2021     F-798 shims and fwd spar. - (6 hours)       Category: Empennage

Made these shims per print, clamped in place & match drilled. located and drilled inner holes on fwd spar to #13, but turns out I don't have the right size collet to chuck a 3/16" reamer or drill bit into my 90* drill motor. Nor do I evidently have an inch long 3/16" drill bit.

i suppose I could try to ream these up from the bottom with a reamer in my air drill, but there's no reason to make it that hard on myself, so i'll run to the yard store and buy the appropriate bits tomorrow.

Read ahead in the plans for a while, little housekeeping around the shop, then primed the inside of the 1.5" tube stock used for the big elevator pushrod. I pulled a rag wetted in acetone through it first, then taped a rubber glove over one end, squirted about 1/2 a can of tempo primer in the other end, and sloshed it around. I'll let it dry for a day or two before I rivet the ends on.

That reminds me, I need to look on VAF to make sure that the dimension called out on the print is safe to use in this case. I know that a ton of guys have had problems with the dimensional callout for the aileron pushrods being too short for safe thread engagement, so they preach that you should make those a little long.

Since I was in primer mode, I also took care of another small task I've been meaning to finish for a while; cleaned up and primed the tailwheel spring and associated hardware. I'll paint it with rattle can epoxy tomorrow to match the weldment and then re-grease the polished portions before rust has a chance to take hold.

  Sep 18, 2021     Started H/S installation - (6 hours)       Category: Empennage

I'm embarrassed to admit how nervous I was about drilling the first two holes in this process, but the you google this task, you get a multitude of build sites about people who've had problems with blowing edge distance here.

The problem is that once you get the horizontal stab located and triangulated to ensure it's where it's supposed to be, you have to lay out a hole location that works for the HS-714 angle on the fwd spar, but also works for the F-718 Longeron and the F-710B spacer. These 3 angles are stacked up with the aft deck covering the lower two and they're oriented at approx 85* to each other. Doing the arithmetic, there's 8 separate opportunities that I can think of to blow edge distance on a structural component with that one hole, and you have to put one on each side of the airplane.

Of the three, the F-710B is the least critical, and when people have run into trouble here, Van's has previously approved some pretty skimpy edge distance on this component. In fact, I saw a couple of build logs online where people had received quickbuild kits with with this part woefully shy on e.d. On the other hand, they are not nearly as forgiving if you blow the e.d. on the longeron. The fix for that has quite often been to add doublers, which I want to avoid if at all possible. I'd really like to get his right the first time.

Way back when you first start building the fuselage, you fabricate the F-710B from angle stock and rivet it to the bulkhead, then way later in the process the F-718 main longerons stack on top of it; Make it too long and it won't nest in the radius of the longerons properly- too short and you blow the already meager available edge distance. If you see that this might be a problem, too bad so sad. You can't pull the hole inbd without blowing e.d on the main longeron, doom on you.

With that in mind, about a year ago when I was working on this part I had made the length as precise as I was capable of, and radiused the end so it would hopefully nest snugly in the corner of the longeron when the time came. I spent quite a bit of time on it to give myself the best chance of success.

As I mentioned, out of all the components involved, the F-718 longerons are the most critical. The build instructions are very specific that you should strive to put this hole dead center in the middle of the space available on the horizontal leg, which works out to be 5/16" from the edge and 7/16" from the apex of the angle. The implication is that if you have to fudge it somewhere, this is not the place to look.

Step one was to verify that the fwd edge of the HS-714 angle matched the fwd edge of the F-710B, which at this point is hidden under the aft deck. I tried a couple of things to measure this and ultimately decided that the simplest way was to stick a plastic protractor under there with the flat edge butted up to the F-710B, then draw a line on the protractor around the edge of the lightening hole, then pull the protractor out of the hole, line up the circle I just drew, and then draw a line on the aft deck along the straight edge, thus transferring the edge of the F-714 to the top side where I could see it.

Once that was done, I transferred the edge of the longerons to the aft deck by simple measurements, and verified that the rivet line down the edge of the aft deck was basically the line that I wanted.

I then positioned the horizontal stabilizer side to side, clamped it to the vertical bars at the aft spar and discovered that sure enough, the fwd edge of the hidden F-714 was about 1/16" fwd of the visible edge of the HS-714. Both of those angles are 1", so there's plenty of meat there to work with as long as you know about it first. I measured back 3/8" from the fwd edge of the HS-714, which will give me 2d edge distance longitudinally on that part and about 2.5 e.d on the F-710B. Potential longitudinal catastrophe accounted for.

NOTE- Both HS-714 and F-710B are 1" angles, and it could be tempting to push this dimension up greater than 3/8" to center the hole on the available 7/8" of the horizontal flanges on these angles, but if you push the hole aft of 3/8" youre going to run into edge distance problems on the aft corner of HS-714 where there is a radius at the termination of the horizontal flange. Do yourself a favor and measure in every direction possible and really think about it before you commit yourself.

I then transferred an intersecting line from my longeron rivet line to find the sweet spot. So far so good. At this point it looks like this will work, as long as it doesn't get too far out of whack when I do the final positioning of the H/S.

I had drawn a longitudinal centerline on the aft deck and had lined up the center butt joints of the H/S spars on it, but now I got out the tape measure and verified that it is correctly positioned laterally. It was off by about 1/16" or so, and I nudged it back and forth until I got it where I wanted it, measuring from multiple points a bunch of times during the adjustment.

Once it was right, I started triangulating the tips with various points fwd on the fuselage.

After I had it right, I left and had a cup of coffee. Came back and measured again. Had another cup of coffee. Measured again. Tips were maybe off by about 1/16" Adjusted, found a different point to measure from. Decided that it was no good to measure to the h/s tip because one skin might be filed back slightly more than the other at the leading edge to account for the gap in the elevator horns. Remeasured from the firewall to the outermost rivet at he fwd H/S spar. Measurement was just shy of 161-9/16" on the right side, 161-11/16 on the left side. Is it really out or is the tape just sagging? Took a break and went to Costco with RJ and picked up a Freddys burger for lunch.

You get the idea- basically, I had worked myself up into a freak out state about this stupid thing and just needed to walk away for a while.

Came back and got the measurement consistently between dead nuts on or within 1/32" depending on where I measured from, clamped it down tight and called it good.

Went back and verified my sweet spot was in the same ballpark. When trying to lay out a hole this precisely, even a thin point sharpie line is pretty fat, so I used a my favorite thin steel scale to exactly reference the dimples in the top of my reference rivet line, and popped a starter hole with a center punch. Once I was sure it was absolutely perfect, I pilot drilled with a 6" #30 bit, then stuck a #30 bit in the hole because it would hold it more perfectly that a cleco, and drilled the other side.

After all that sweating and scheming, they came out just about perfect. The result was exactly 5/16" e.d on the longerons (per builder instructions) good e.d. fore & aft, and 4/32" e.d. to the end of the F-710B on each side, which is honestly, about as good as is physically possible, given how this all stacks together.

Holy cow, I'm glad that's over. I feel like I just defused a bomb.

Tomorrow I'll fabricate the shims that go between the HS-714 and the aft deck, upsize these holes to final size and drive forward.

  Sep 17, 2021     Drilled elevator horns - (4 hours)       Category: Empennage

I'm just about at a stopping point on the fuselage kit until I get my engine and avionics- Avionics so that I can lay out the magic boxes and see what mods I need to do to the substructure, as well as running the wire bundles, and engine because I'm going with the IO390 and vans doesn't have any guidance on firewall penetrations for that setup, so I cant finish running fuel lines or anything else until I have the engine.

So, I've decided to jump into some big ticket tasks I've been putting off. I don't have help this week to mate the wings, so I'm going to work on the empennage.

I got the elevators and H/S out of storage and pulled the blue vinyl off of them. They had been in my furnace room for over a year, and after about 6 month I had the fleeting though that I should maybe go pull the plastic off of them in case they were starting to corrode underneath, but of course I got busy with other stuff and never did it.

They weren't corroded at all, but I had covered the rivet lines back up with tape, and the glue had turned to tacky mush, and I spent a good bit of time scrubbing them with acetone to get everything off of them.

The first thing that you do at this point is to re-hang the elevators, clamp them in trail, and drill the pushrod hole in the end of the control horns. There's nothing special about doing this now. I don't get why they don't just tell you to do this when you're working on the empennage kit.

Anyway, the plans indicate that usually the horns are not exactly symmetrical, and while mine were close, sure enough, one of them was slightly aft of the other when both elevators were clamped in trail. I laid out the dimension and drilled the hole on the most aft horn per the instructions. The hole is called out as 3/16" for a -3 bolt, But at this point I just pilot drilled it to #30.

The plans are very specific about the two faces of the horns being exactly parallel during match drilling, and tell you to make a drill block out of hardwood or aluminum that's the exact size of the gap and clamp it between the two horns to match drill the second horn from the hole you just made in the first.

I miked the gap and in my case, it's about .902" I don't have a reasonable way to make a block thats exactly .902" so I started rummaging through my specialty tools and clamps and whatnot looking for a solution.

Ultimately, I settled on a drill guide and a couple of washers and was able to drill the other one without issue. I reamed them up to full size and they appear to be symmetrical. I will be able to tell if they are exactly right if the elevators are still parallel when I tighten down that bolt on the elevator pushrod, but I measured them after reaming and I couldn't see any deviation. I know taht they are at least as good as I could have gotten with a wooden block.

  Mar 07, 2020     Rolled rudder leading edge - (2 hours)       Category: Empennage

Had all day available Friday, But instead of working on the Rv I went for a marathon flight with Robert in his Glass Star. He has a goal to land at every public use airport in KS and He had Friday off as well. He had flight planned 26 airports, but we were both beat after lunch at Miami county, so we cut it short and headed home. 5.6 hours and I think 19 airports total. lots of grass strips, the shortest was 1600' plus a landing at MCI and cheap fuel at downtown. Lots of frequency switching, especially hitting the class B. He only has one comm in that plane and knob twisting on that flight confirmed my opinion that I'm definitely a 2 comm guy.

On Saturday morning I rolled the leading edge of the rudder. Man I'm glad all that flight control rolling is done. Not fun. Also installed the heim joints per print, but the bottom one doesn't line up and the specified dimension, so some tweaking will be required.

Robert showed up to hang out around noon, so I put it away and moved on to a couple of bigger jobs while I had him around to help.

  Mar 05, 2020     Rudder trailing edge - (2 hours)       Category: Empennage

The rudder has been sitting for about 5 days while the pro seal cured, so today after finishing up the elevators I thought I'd bust out the trailing edge. Unclamped/clecoed the trailing edge, and spend the next hour or so cleaning out the excess pro seal ooze. First I twirled a #40 drill bit in the hole then finished up with a q-tip dipped in acetone.

After cleanup, I numbered each hole 1-5 and then marked each 10th hole as well.

Vans plans have you back rivet the t.e. which seems like a recipe for disaster, so I bought a set of trailing edge dies from Cleveland Tool. Holy cow, that was money well spent! I started with every hole clecoed, alternating sides, and 1/2 set a rivet in each 10th hole. Then every 5th hole and so on, always positioning the rivet so that the factory head was on the side that he cleco came out of.

After getting a rivet 1/2 set in every hole, I went back and fully set them, starting more or less n the middle and working my way to the ends.

It's hard to capture with a cell phone camera due to focal length, but it came out pretty darn straight. Just have to roll the leading edges and install the heim joints and this rudder is done.

  Mar 05, 2020     Elevators finished except fiberglass - (3 hours)       Category: Empennage

The first task completed was to add nut plates to the front tooling holes on the counterbalance horns. It's not per print, but other builders have done this because it's an easy place to add washers after the fact if you need to add weight up front to rebalance after paint.

After that, I set the heim joints to 13/16" per print, which resulted in the counterbalance horn gap growing from 1/8" near the hinge line to about 3/16" at the tips. This is consistent on both sides and I I could fix it by backing out the inbd heim joints to the max allowable 7/8". I toyed with the idea of doing that for aesthetic reasons, but input from VAF pointed out that if they weren't both more or less the same, it would make the control horns not be in the same plane when they rotate. The general sentiment was that it's better to have everything as in plane and friction free as possible rather than try to tweak for a tiny gap variance. This seems like good advice, so I set all the heim joints to 13/16" and moved on.

Checked for binding, range of motion, etc and everything looked good so I pulled one elevator and then went ahead and drilled the control horns on the other one for the AN4 bolt that goes through the center bearing. The bushing I used to center the drill bit was a simple aluminum 1/4" bushing that I got at ace hardware for about a dollar. Even though the bushing was supposed to be 1/4", it was microscopically bigger than the bearing, so I chucked it up in my drill press and used some 2000 grit sandpaper to turn it down until it was a slide in fit. I slathered on some Boelube, held the bushing so it wouldn't spin the bearing, and went to town. After drilling with the bushing, I pulled the elevator and sized the hole up for a AN4 with my electric drill because I can control the speed a little better that I can with my air drill. Pulled that elevator, installed the other one, and repeated. Everything worked fine, the bolt slides right in, and at this point I'm calling the elevators done except for torquing down the jamb nuts and fiberglass work.

  Mar 03, 2020     rolled elevator leading edges. - (9 hours)       Category: Empennage

So this entry actually covers 2 days; Yesterday I rolled the leading edge for the right elevator and spend about 5 hours struggling with it. I used a 1.25" galvanized water pipe that I had laying round and thought that I followed the process as specified in section 5. However, it was a real struggle to get the overlapping top edge to lay down flat.

It seemed like no matter how much I finessed it, either the top layer was bowed up at the edge or between rivet holes, or the bottom layer was bent so much that I couldn't pull it tight with just clecos. I messed with it for at least a couple of hours before I got a passible result, but it still had some pillowing between the 6 outbd rivets on the center section.

I researched it afterward and people have reported better results with less effort if they bolt the pipe down with J bolts thru the table top at the hinge cutouts. Also, I got the impression that the pipe diameter was maybe a little too big.

Today, I went to Ace and picked up a couple of j- bolts with about a 1" inside diameter, and took the handle off a leaf rake I happened to have that was 7/8' diameter, to see if I could get a better result.

While it was definitely easier to roll with this setup, I gotten exact same result. I fought with it for a couple of hours, and then just admitted defeat and riveted it with pillowing in exactly the same area. I went back and pulled 5 extra rivets between the OEM locations on both elevators and they both look good at this point.

Don't know what I did wrong here, but If I ever build another elevator set, I'll go right to the extra rivet solution the second I see a problem and save myself several hours of frustration.

  Feb 29, 2020     L/H Elevator & Trim Tab. - (8 hours)       Category: Empennage

Spent way to long on this and forgot to take any pictures, but Robert August came over again this morning and we spend about 8 hours hanging out in the garage and finishing up the l/h elevator & trim tab. It all came out ok except the instructions have you close up the trim tab with no mention of dimpling the holes in the ends.

I didn't catch this until after riveting the tab spar per instructions, and then looked at the rivet callout on the print and discovered that while the rivets on the elevator closeout are pan head MSP-42's, the ones on the tab are supposed to be CS4-4 flush head. I can't see any way to dimple those holes unless you take everything apart again, which I'm not going to do just for a couple of soft rivets.

Drawing 4 calls out an MSP-42 pan head pop rivet for the elevator closeout, so I used these on the trim tab as well, making sure to lay them out in a position that won't cause interference. The MSP-42 is a monel rivet with a steel shaft, so It's quite a bit stronger than the CS4-4 that's called out for the trim tab. Structurally, they will be fine, but at some point in the future if I decide I cant stand the look of the pan head vs the flush CS4 I might revisit this.

For now, I'll roll the leading edges in a day or two, then the only thing left on this empennage will be to pin the elevators and drill the center hinge hole.

  Feb 29, 2020     Elevators, trim tab & rudder in process - (6 hours)       Category: Empennage

I've been saving up the pro seal jobs to do them all at once, so today I mixed up a tube of B-2 & squirted a dollop on the elevator stiffeners and the rudder trailing edge wedge, then closed everything up.

Finished the r/h elevator other than rolling the leading edge. Clecoed the l/h one together, & clamped up the rudder trailing edge to set up.

Some people report difficulty getting the rudder trailing edge straight, so instead of the 3m tape I elected to go old school with pro seal because it gives things the ability to be wiggled around a little before it sets up. Once I had a light coat of proseal applied, I sandwiched the t.e. between 2 heavy angles with clecoes, alternating direction in every hole. After that, I went back and added cleco spring clamps between every cleco, also alternating directions. Even though I had a pretty thin skim coat of pro seal to start with, I saw some squeeze out at that point, so hopefully I won't get any pillowing between the holes. If it's not straight after this I really don't know how I could do any better.

I started with the rudder laying trailing edge up and the counterweight hanging off the edge of the table, but eventually, the weight of all that stuff hanging off of it made it so top heavy that I had to lay it down, but by that time I had almost every clamp in my arsenal hanging off of it.

I wanted to make sure and get everything done and positioned before the B-2 started to set up, so I didn't take the time to take pictures of anything except the results.

I had some B-2 left over, so I took advantage of that the way we used to back in the day and stuck a $0.99 magnetic screwdriver tip in the end of the tube. When it cures, you can cut the tube away and you have a screwdriver with a giant grip that you can put an apex bit in and apply a crazy amount of torque. Used to use these all the time to take pylon fairings off the jets and somehow the last one I had went missing years ago.

  Feb 26, 2020     L/H elevator - (5 hours)       Category: Empennage

Match drilled, dimpled/countersunk, primed faying surfaces, folded trim tab closeout etc. Everything came out good.

Ran into a situation on the 4 holes upper & lower in the trim spar that are outbd of the closeout fold. I don't really see how you could match drill them before doing "the big fold" so I didn't, but then there wasn't a way to get either a squeezer or c-frame on them to dimple afterward without unbending the skin.

I thought about it for a while and ended up drilling a #10 hole in the oak wedge that I had made for bending the tabs so that it would hold a female #3 dimple die. I was able to slide it into the skin without unbending anything, put the male side in a cheap 7/32" socket and then smacked it with a BFH to make the dimples. came out really nice.

I'm pretty happy with how the trim closeout flaps came out as well. The secret is to tape the entire hardwood wedge with really sticky double sided carpet tape, then clamp it to the table & tape all of the edges of the whole elevator to the table as well so that nothing can move at all.

  Feb 22, 2020     R/H elevator substructure - (2 hours)       Category: Empennage

match drilled all the R/H elevator structure to the skin, deburred & primed the skeleton as well as the feying surfaces on the inside of the skin with zinc phosphate primer.

On the old elevators I got with my wings, I discovered a big air pocket inside one of the lead counterweights, so prior to match drilling for these weights, I weighed them both on my postal scale to make sure they were more or less solid. They both weighed 2lb 7.1oz, so that's good.

One note of caution; They have you temporarily install the counterweights then drill through them for the AN bolts that hold them in place via a couple of pilot holes that are in the tip of the counterbalance horn. The holes on the back side need to pick up a couple of different flanges, and I can see how if you didn't drill straight through you could either run into an edge distance problem or alternately, get to close to the web so you couldn't get a lock nut on the back side. Based on that, I used a drill guide block and it came out fine.

  Feb 21, 2020     Elevator stiffeners - (4 hours)       Category: Empennage

Robert August came over and hung out in the garage this afternoon and we dimpled & riveted all the stiffeners on both elevator skins. It was a big help to have an extra set of hands in maneuvering the skins in the DRDT@ dimpler.

It was also helpful to have a second set of hands available during the back riveting; In order to get the back rivet set on the rivets closest to the trailing edge, you have to pull back the upper skin, which causes the lower side to want to raise up off the plate. A second person can use one hand to hold the upper side back, and another hand to push down on the lower skin to make sure it's firmly on the plate.

I've known Robert since A&P school and recently taught his daughter to fly. Was fun to spend teh afternoon hanging out.

We also bent the trailing edges in the homemade brake I attached to one edge of a workbench. I deviated from the section 5 plans in how to make this brake; Vans shows that you should hinge 2 2x8 or 2x10 sections together so that the long edges come together to make the bend. I've seen others on VAF set it up so that the bending faces are the narrow edges, and it seems like this is the way to go. You can see what you're doing better, and by clamping a couple of wood clamps on the upper board for handles, you can get as much leverage as you would ever need.

I bent these with a 1/8" wooden dowel rod in the trailing edge as insurance against creasing the skin and it worked out great. There are a couple of areas where there is a slight fall off at the trailing edge, and I was able to massage most of that away with the wooden block hand seamers that Vans also suggests you build. Ended up with really straight trailing edges that I'm happy with.

You may recall that this is my second go-around with these elevators, and on the first one, I ended up with the 720 a b &c stiffeners with the flanges opposite the rest. I assumed that I had made a mistake in cutting and tapering these, so when I got new stiffeners, I was very careful to mark out the cuts based on the tooling notches that are already on the pieces you cut these out from. Sure enough, there is only one way to cut these, and those 3 sets are backwards to the Isometric view on the print. I had already talked to Vans and they said it's irrelevant which way the flanges faced and some guys on VAF said that some of them are stamped backward and that's just the way it is.

  Feb 20, 2020     new elevator skins & stiffeners prepped. - (4 hours)       Category: Empennage

fabricated stiffeners, match drilled to r/h & l/h elevator skin. primed stiffeners & mating surface inside skins with tempo zinc phosphate primer.

  Feb 09, 2020     perfection is the enemy of progress, but... - (4 hours)       Category: Empennage

Well heck. I bent the elevator trim tab ears & all is well, but when I went to do the same on the elevator, my backer block slipped and I got the trailing edge bent a little too far outboard. What this means is that the gap between the elevator and the trim tab is bigger at the trailing edge than fwd. It's perfectly airworthy this way, but just looks sloppy, and I'm not in the business of putting my name on sloppy work. I know that others have cut those ears off and built ribs to go in there, but in this case, that would lead to a pretty big gap between the tab & the elevator, and I'm shooting for tight lines.

Simply put, I've ordered another elevator skin to do this again. I'm redoing the right side as well, since some of the stiffeners are mirrored and I'm paying for shipping anyway. 2 new skins & stiffeners are about $150, but it's money well spent know that I'll have pristine flight controls.

If bending the ears doesn't work on round 2, I'll accept defeat and build end ribs like so many other people have.

  Feb 04, 2020     riveted elevator stiffeners - (4 hours)       Category: Empennage

Dimpled & riveted elevator stiffeners & trim reinforcement plate.

  Jan 31, 2020     rudder/elevators - (7 hours)       Category: Empennage

Was gone for about a week on a work trip to Europe with Kriya, and while I was gone, the new rudder wedge arrived from Vans as well as the fixture from Cleveland tools to aid in countersinking it.

Countersunk the new wedge to .007" below flush per guidance from Vans. The edge doesn't really look any better than the first one, so hopefully it will pull up a little bit more when it's bonded/riveted, but this may be as good as it gets. Per Van's, this is definitely as deep as those countersinks should be.

I'm on the fence about whether to use 3M tape vs. pro seal on the rudder wedge, but went ahead and started the elevators so that If I decide to use pro seal I can do everything with one batch.

There are 3 locations on the left elevator where the E-720 stiffeners get a little extra trimmed off the trailing edge. The aft-most hole isn't pilot drilled on them, so even though there's a dimensional callout for how much to shorten them, I went ahead and clecoed them on and match drilled them to make sure I wasn't going to run into an edge distance problem after trimming. I didn't need to bother, there's tons of e.d. left over after trimming to the print dimension.

While I was doing this, I discovered that somehow I had evidently tapered the wrong end of the stiffeners at the 3 inbd-most locations on the right elevator. Everything lines up fine, but it means that the flanges are mirrored and facing the opposite direction of how they are depicted on the print. I stared at it for probably 1/2 hour trying to figure out if that's actually what had happened or if I just had them swapped somehow, then went to research vansairforce for about another hour. I have no idea how this is even possible because the trim lines are just by created by connecting the dots between notches that are already in the angle, but evidently It's easier than you would think, because I'm not the first guy to do it.

I couldn't see how it would cause any problems, but I decided when I started this that I'm going to get factory coverage for any deviation from print that isn't covered by AC43.13 or standard industry practice, so I fired off an email to Van's and they confirmed that it didn't matter which way the flanges faced as long as the top and bottom on each set are opposing so they don't interfere with each other.

Based on that, I pressed on and match drilled, trimmed, and de-burred the stiffeners and skins. Probably 2 hours of work that I managed to stretch into 7, but I'm happy with how everything is going together.

  Jan 16, 2020     worked on rudder, started elevators - (7 hours)       Category: Empennage

Finished riveting everything on the rudder except the leading & trailing edge. I'm still unhappy with the fit of the trailing edge wedge. I sent the picture below to vans support, but it looks to me like the dimples aren't nesting properly. I don't see how I can countersink it any more, because it's already knife edged. I'm thinking maybe the countersinks aren't perfectly aligned with the face of the wedge.

Cleveland tools sells a fixture to hold the wedge flat so that you can countersink with a microstop in a drill press, so I ordered one of those today and a new wedge from Vans. Once they arrive I'm going to try it again and see if I get a better result. I've seen pictures of other guys who had the same problem and filled the t.e. with pro seal or epoxy after the fact, so that may be as good as it gets, but it just bothers me that it doesn't seem to fit better than that. I also emailed the tech support guys to see if they had any suggestions.

Took a break while I was thinking about this and went down to the yard store and bought a 5' long chunk of 3/8" thick aluminum angle to make sure the t.e. gets bonded up straight when I get that far. One of the bonuses of living here in Wichita. They sell aluminum by the pound, and that piece of extrusion only cost me 9 bucks.

When I got back, I went ahead and fabricated all the elevator stiffeners. Tomorrow I'll likely start on the elevators and come back to this rudder issue in a few days.

  Jan 15, 2020     Rudder - (10 hours)       Category: Empennage

Made a #10 dimple die out of a thick piece of aluminum and just used the screw pulled through it to make the counterbalance rib dimples. I used a similar process for the dimples on the skinny end of the ribs, although there I held the bar in a vise, taped the male die inside a socket and then whacked it with a hammer. Worked fine.

Clecoed everything together one final time, then started final assembly.

The print that came with the rudder parts isn't the latest rev and doesn't show the nut plate strap on top of the counterweight, although my preview plans do. Turns out it was in a bag with the hardware so I went ahead and constructed it instead of just using washers & lock nuts on the end of those screws.

Started riveting on the skins the ones in the counterbalance rib/skin/spar interface are a bear to get to, but fortunately I have a small tungsten bucking bar that fit in there. I was able to squeeze most of the rest of them. Haven't decided yet what to do with the skin rivets where the tails are inside the horn brace. If I buck them, I'll have to work through a 2" lightening hole, but I don't know if I can get to them with a squeezer. Something to figure out tomorrow.

The t.e. has a slight gap around the wedge, like maybe the dimples aren't nesting properly, but I've countersunk that wedge until the holes are knife edged (acceptable in this application according to vans) and I don't think going deeper will do anything except wallow the holes out. I looked on vans airforce and lots of guys have reported the same thing. All sorts of solutions have been tried, but most guys seem to just live with it. I'm going to sleep on it and see if a solution occurs to me.

  Jan 14, 2020     Match drilled, deburred & primed rudder parts - (7 hours)       Category: Empennage

trimmed/fabricated all rudder parts, assembled, match drilled, deburred & edge finished. Primed skeleton & mating surfaces.

Was going to drill/dimple for the rudder counterweight while I was waiting for primer to dry, but couldn't find a dimple die for a #10 machine screw. Thought I had one somewhere, but I guess not. Will pick up one tomorrow as well as a straight edge angle for the rudder and a couple of other things at the Yard Store.

Unless something pops up, I'm planning to get this rudder together in the next day or two and then knock out the elevators.

  Jan 10, 2020     finished rudder stiffeners & started spar skeleton - (1.5 hours)       Category: Empennage

Once everything us set up, back riveting the stiffeners to the rudder skin goes really fast, so today the r/h side only took about 45 minutes.

After I finished it, I started in on the rudder skeleton, which is the next step in the plans. Nothing super hard about it. The first step has you Cleco the lower rib to the spar and drill the pilot hole in the rib flange out to 3/8" to match what's already in the spar web. Eventually the heim joint that makes up the lower rudder hinge goes through there. I started with a uni-bit to get it up to size and then finished with a 3/8" bit in a cordless drill. Came out okay.

There are extra holes in both the rudder control horn and the reinforcing plate that aren't on the spar. In the picture below, I've circled them with a sharpie. They are also not shown on assembly print 7, so I checked with Vans. The word back was that they are there for the RV14 and I can either ignore them or match drill the spar and rivet them, my call. Would have been nice if they had included a note to this effect in the plans.

  Jan 07, 2020     rudder stiffener install - (5 hours)       Category: Empennage

Drilled apart the practice airfoil and re-assembled it a couple of times to make sure I was comfortable back riveting the thin rudder skins, then dimpled stiffeners, skins, and installed stiffeners per print on 1 rudder skin. Ran out of time today, so I'll get the other side in a day or two.

I see people build all sorts of complicated dimpling and back riveting tables, but It seems like that's a lot of effort for something that isn't really used a ton, so for dimpling skins, I just set the DRDT on a old coffee table and built up a surface on each side of it with the cardboard box the skins came in. For a back rivet plate, I used a 6" by 18" chunk of 3/8" thick steel that I bought at the yard store for about $10, with a moving blanket folded up on either side of it to make everything level.

  Dec 27, 2019     Rudder stiffeners - (4 hours)       Category: Empennage

Fabricated all the stiffeners per print, match drilled, de-burred and primed. Then left for about a week of holiday travel.

  Dec 09, 2019     rework galore. - (5 hours)       Category: Empennage

Got the mis-drilled hole in the R/H Elevator control horn welded up, but there were several deep grind marks where the welder smoothed it down that I wasn't happy with. Since that elevator had set marks in the skin in a couple of places, I elected to just rebuild it.

Before I ordered parts, I thought I'd go ahead and do SB14-02-05 for elevator spar cracking on the left one, since I already had the SB kit and that way if I messed it up, I could order another elevator and not have to pay twice for shipping. The SB wasn't hard to do, although I had to grind down the side of a pop rivet puller to get clearance on one of the new cherry rivets.

To my utter disappointment, afterward, the L/H elevator no longer seemed to line up with the center bearing. When I pinned it onto the H/S, at the middle and outbid hinges, the center bolt didn't drop home like it had before. You could slide it in with just light finger pressure, but could hear and feel the threads rasping on the hole in the control horn as it slid in.

I originally thought that one of the nut plates that the heim joints screw into must have shifted when I reinstalled it after the SB, but I knew that I hadn't oversized the holes, so if that was the case, it would have been a microscopic change.

I logged 5 hours for this entry, but troubleshooting this and head scratching took probably double that. Ultimately, I discovered that the hole that the previous kit owners had drilled was perfectly aligned when the elevator was in trail, which is what I had experienced when I did the trial fit a few weeks ago, but wobbled by about 1/64" out of plane when I swung the elevator up or down. It wasn't enough to even see with the naked eye until it reached pretty much full up or down travel.

This is a tiny alignment issue, and at first I assumed it was because the elevator horn weldment was maybe crooked where the tube welds onto the flange that rivets to the spar and end rib. Honestly, if I hadn't already been planning to rebuild the other one, I would probably just have lived with it, but the hinge line for the trim tab isn't perfect, and since I was planning to rebuild the r/h one anyway, I elected to just do them both, so I'll have a matched set.

I got curious about whether this might have been the same situation with the r/h elevator control horn mis-drilled hole, but I had already unskinned it to see if I could reuse the spars etc so I couldn't re-install it to see if the hole lined up in one position vs. another.

On the r/h elevator, once I got it unskinned I had discovered one of the E-702 spar to E-704 counterbalance rib rivets had some sort of catastrophe, and they had replaced it with a giant LP style pop rivet, including a 1/8" doubler to account for the extra grip length. I ditched the idea of reusing anything except maybe the counterweights at that point.

Since I was already in autopsy mode, I now went back and drilled the control horn off the r/h elevator skeleton out of curiosity and discovered that on the 4 rivets under it that are common to the E-702 spar & the E-709 root rib, all of the countersinks were proud by probably at least 3-4 thousandths. I don't know if this would be enough to cause the control horn to sit crooked and hose up the alignment, but it certainly didn't help.

Thought that I could probably salvage something out of this, so I went ahead and profiled the counterweights, which hadn't been done, and cut down the r/h one per print while it was still attached to the tip rib, so I'd have something to hold onto while cutting it on my band saw. I then drilled off the counterweight skin and removed it. Was only a little surprised at this point to see that they had evidently forgotten to install it before riveting the skin onto the ribs so they had grooved around the countersinks in order to be able to slide it in after the fact.

Since I was ordering parts anyway, and given the learning curve they were evidently going through at this point in the build, I decided to build a new rudder as well. On the old one, the skin has a mushroom set mark in it and there is a 1.5" long gouge from hangar rash pretty much right in the middle of one skin. My original plan was to just have these addressed with a few grams of sand and fill during paint, but the more I think about it, the more I don't want to "settle" by having filler on a flight control, especially one that has historically has issued with skin cracks. It's a slippery slope, But I'll sleep better knowing that I've put together all the tail surfaces per print/mil-spec and there's no hidden band aides in areas that can't be inspected once everything is closed up.

I'm glad I got this kit on the cheap, and that I really just bought it for the wings, because at this point the only component of the empennage that I'm not rebuilding is the v/s, which appears to be fine and unblemished.

  Nov 23, 2019     Drat- the control horn to center bearing hole is mis-drilled - (2 hours)       Category: Empennage

The center bearing hole in the elevator horns was already drilled by the previous builder on these, so when I was doing the temporary fit for trimming the 603PP spar flange and the h/s skins for counterweight horn interference, my assembly process was to stick a bolt through the center bearing, slide the elevator inbd onto the bolt, and use that pivot as a 3rd hand while I got the center and outer Heim joints lined up and rig pins installed.

On the left elevator, everything slipped together no problem, but on the right, you had to wiggle that last (middle) rig pin a bit to get it installed. I started thinking about this after my last log entry so I went back and revisited it yesterday. After a few minutes of staring at it, measuring & whatnot, it became obvious what was going on; Either the other guys mis-drilled the hole originally, or I had an unfortunate tolerance buildup when I rebuilt the H/S. Whatever the case, the bolt hole in the R/H elevator horn is off by about 3/64". I didn't notice this at first because I pinned that end, then the tip. The last thing to go together was the middle heim and there's enough flex in the elevator that you can get the pins in even with a slight mis-alignment.

Unfortunately, this isn't a case of mis-adjusted heim joints. The hole is fine fore/aft, and all of the skin lines & other dimensional measurements are spot on. The hole is just off vertically by about 20% of its total diameter. This is a little frustrating. I can push the control horn down with my thumb and easily get it to flex enough to get the bolt to slide home, but It's not right, and I think at the very least, it would probably cause either the center bearing or the r/h middle heim joint to wear prematurely.

I emailed van's just to make sure I wasn't being overly picky, and the response from Sterling Langrell was short & to the point;

"Have this hole welded closed and drill it properly. If you force the bolt in you will have nothing but trouble latter down the road and possible cracked spars."

Sigh. Hopefully I've got an easy fix. The guy who blows out our sprinkler system every fall does that as a side gig. His actual job is a welding inspector at a big facility here in Wichita. I called him yesterday to see if he though he'd be able to hook me up and he said no problem. He's got a TIG/MIG setup in his garage. I'm headed over there this afternoon to see if we can get this fixed.

  Nov 20, 2019     trimmed HS702 and H/s skin interference - (4 hours)       Category: Empennage

Today was a lot of putting together, marking, taking apart, trimming, putting together to check for fit, taking apart to clean up edges, etc.etc.etc.

laid out the areas to remove for the 603 aft spar flange/elevator control horn interference and the elevator counterbalance horn/HS skin interference. both of these areas are a case of measure twice cut once, so I took my time.

Once everything was laid out, I drilled the corners and then cut to the holes with an abrasive wheel on my dremmel. I cut inside the lines and then finished up to the line with a vixen file. Radiused the corners with a chainsaw file (new file, never used on steel, so as to not introduce the potential for any dis-similar metals corrosion) then dressed out all the file marks with 400 grit sandpaper. Everything came out great.

During the operation, I taped the blade from a stainless steel putty knife to the substructure as added insurance to protect it if the dremmel got away from me,, but it never did.

EDIT- There was a problem lurking in here that I didn't think about until laying in bed this evening after writing this original entry. Ref 11-23-19 empennage entry for details.

  Nov 19, 2019     Temp install elevators - (2 hours)       Category: Empennage

Decided to temporarily install the elevators so I could get a measurement for trimming the lower flange of the HS602 aft spar for the elevator horns. There's also interference with the counterbalance horns and the 601PP skins that will need to be dealt with.

The print doesn't call out a dimension for the cutout of the 603. Basically it just says trim as needed to allow the horns enough unrestricted movement to get appropriate elevator travel. The only way I could see to precisely locate this was to temporarily install the elevators so I could see how wide to make the cutout.

When I bought this kit used, I got a couple of big tubs of random stuff with it, including an envelope of temporary hinge pins. Turns out that until the skin interference is trimmed, the elevators are stuck in trail and there isn't enough room to get much access to the hinge points, so after fighting with this for a few minutes, I went to the hardware store, bought a stick of 3/16 brass rod, and made my own rigging pins with a handle sticking up that made it a lot easier.

The side to side dimension of the control horns turned out to be almost exactly 1.75 inches. I wasn't sure how much extra gap people typically leave on each side, so I called Vans. Sterling said most people shoot for maybe 1/8" there. I also asked him how much gap to leave around the counterbalance horns because I couldn't find it on the print anywhere, and he pointed out that It was in the top left corner of DWG 3 and calls out a min 1/8" gap.

Started laying out dimensions, so I'll try to get his stuff trimmed up tomorrow.

Will probably also trim up the lead weight per print while I'm cleaning up stuff, but there's nothing urgent about that.

  Nov 18, 2019     Finished Horizontal Stab Assy - (10 hours)       Category: Empennage

Had a 0600 flight student, but other than that and taking RJ to work at noon, I spent the rest of the day in the garage with the door up. Constantly amazed by how crazy the Kansas weather can be. Last week it was down in the teens overnight and today it was 70.

Assembled Horizontal Stab assy per print & Vans written instructions. Had to drill out a couple of rivets, but no drama involved. Everything went together nicely.

The Tempo rattle can primer I used on the ribs and whatnot isn't very robust, and I scratched it in a few places taking clecos out, so I fogged the inside again before installing the HS603 Aft spar. It's good enough for substructure as long as you're careful, but I'm definitely going to have to find a better solution when it comes to the cockpit.

  Nov 17, 2019     assy continues - (1 hour)       Category: Empennage

Clecoed everything together per plan. Ran out of time tonight and had to go meet the family at the movies (Ford vs Ferrari). Only got one flight tomorrow, and it's super early. Should be home by 0900. Its supposed to be close to 70 here tomorrow, so I'll likely spend most of the day in the garage.

  Nov 16, 2019     H/S Spars - (2 hours)       Category: Empennage

Finished assy of HS603 aft Spar & HS702 front spar

  Nov 15, 2019     dimpled skins & riveted in HS707 on left H/S half - (3 hours)       Category: Empennage

Dimpled Skins with the DRDT-2 with some tape on the nose piece to keep from scratching stuff up. The nose rib flanges are too close together to dimple them this way, so I just squeezed them with the dies in a hand squeezer.

The big wooden forms are something I saw on other builder sites. Just traced the outline of a rib on some scrap plywood, cut it out with a jig saw and padded it with a couple of layers of masking tape to keep it from scratching.

When I was trying too get the skin to conform to the nose ribs, I tried all sorts of stuff to get them to lay down, but it seems like the easiest way was to just follow the instructions and lean into the rivet gun a little. It all snugged up nicely with no problems.

  Nov 06, 2019     prep for final assy. - (5 hours) Category: Empennage

Disassembled everything, deburred, finished/relieved all edges, dimpled, then primed the substructure, including the mating surface inside the skin. Forgot take any pictures, but it's all ready to go together.

  Nov 05, 2019     disassembly &b debur l/h horizontal stab - (2 hours)       Category: Empennage

Assembled, & match drilled the r/h horizontal stab. This went a lot faster than left half now that I have some concept of Van's vision of how things go together and in what sort of logical order. I already have some parts ready to go because I had trimmed them at the same time I was doing the l/h half, so it only took about an hour to cleo this together and another hour to match drill it.

It's supposed to be low vis tomorrow morning, so if I cancel my early morning VFR student tomorrow, I'll probably end up spending most of the morning prepping for final assembly

  Nov 04, 2019     dimpled L/H horizontal stab. clecoedR/H half - (7 hours)       Category: Empennage

Deburred & dimpled all components of L/H horizontal. stab. ready for riveting. Turns out that the -3 dimple die I was using was hitting the inside radius of the rib flange, so I had to sand down the shoulder a little on my disc sander. Didn't take much. Assembly of R/H horizontal stab. in process just need to match drill HS00005 & 6 to the spar & skin, plus the spar/doubler/ reinforcing angle holes outbd of the bend line. Once that's all done, it will be time to take this all apart again for deburring & dimpling.

  Nov 02, 2019     match drilled L/H half - (4 hours)       Category: Empennage

This encompasses a couple of different sessions with a total of about 4 hours, not counting research. Finished match drilling the L/H skin and all the support structure. Disassembled and match drilled the HS702, HS714, HS710 & HS00001 doubler inbd of the HS00005 & 6 ribs.

Lots of old posts on the Van's forum about edge distance problems on the ears of the HS00001. You just have to match drill thorough existing holes in the 710 & 714 and you get what you get. The print didn't give dimensions and the default 2d for a -4 rivet looked like it would be unlikely so I was thinking that I was going to have the same issue. Before I went any further, I researched it in depth, and discovered that the SB that installs this part to existing Horizontal Stabs specifically callout a min. edge distance for those rivets of 5/32" I don't know why they don't add that note to the assembly print, for new components because it would save a ton of research trying to figure this out. I measured it out and have good ed per service bulletin, so I'm moving on.

  Oct 29, 2019     finished match drilling & deburring fwd spar assy - (2 hours)       Category: Empennage

Got everything in the center section match drilled, deburred countersunk where appropriate, etc. At this point I'm right back where I was a week ago, but with proper hole spacing and edge distance on new HS702, HS00001, HS710 & HS714.

  Oct 28, 2019     Aft spars, round 2 - (4 hours)       Category: Empennage

Trimmed, fitted, match drilled HS0001 Spar Doublers, HS702 fwd spars. Match drilled, trimmed and bent HS710&714 reinforcing angles per print. Some of these holes get match drilled through existing holes in the 710&714 so they are easy to get perpendicular, but some of them have pilot holes on the thin side that you drill though into the thicker material. Seems to me that it would be pretty easy to drill crooked into the 710 & 714 on those, so I used a drill guide to keep everything plumb.

Tripped a breaker by had a space heater & shop vac running, then when my compressor kicked on it tripped the breaker. No big deal, but for some reason when I reset it, the compressor wouldn't come back on. I think there was something going on with the start capacitor. I took it apart and re-twisted the wire nuts connecting to make sure they were tight it and it fired right up after that. It got me going again, but I pulled the plug from the wall when I shut down tonight, until I can figure out what's going on with it. This is a little frustrating. It's a Kobalt from Lowes, and only about a year old.

  Oct 26, 2019     primer experiment - (3 hours)       Category: Empennage

While I was waiting for new H/S parts from Vans, I thought I'd try an experiment. It's going to get cold next week, and my garage is unheated, so priming will be problematic if I have to wait for perfect conditions. I went ahead and deburred/edge finished all the ribs and aft spar components parts for the L/H half of the H/S before match drilling & dimpling.

I'm using Tempo self etching zinc phosphate primer in a rattle can and all the spec sheet really says is that the bare metal should be clean, the can should be between 50-90 degrees when spraying, that you can handle in 1/2 hour, top coat in 24 hours & that it's 100% hard in 48 hours. My garage was about 50 degrees when I shot this, and I cleaned the surface by wiping down with acetone. I shot these parts before they've been match drilled or dimpled, because I'm interested to see if this stuff gets tough enough to handle a dimple die.

It was dry to the touch within about 20 minutes, but it got down into the 30's overnight and the next day it really didn't seem like it was very hard. I brought the parts inside, hid them in the hall bath and opened the heat register all the way. When the furnace kicks on, it heats that tiny room to about 80 degrees, so I'm going to see how durable this stuff is after baking a couple of days.

  Oct 23, 2019     OOPS! Category: Empennage

Well, drat. I just realized that when I match drilled the HS0001 doublers to the spars, 710 & the 714, that the hole spacing isn't symmetrical re top & bottom, and I managed to get them backward. The 5th hole outbd from center is supposed to be in a line with it's neighbors and I've got them offset. Still have good edge distance, but because that area is extremely structural, I'm just going to order new parts and do it right. Can't believe I made such a stupid mistake.

  Oct 20, 2019     Fwd spar work + made some tooling - (8 hours)       Category: Empennage

Got some oak at Lowes the other day & made hardwood jaws for my vise. While I was at it, I went ahead and built the flange straightening tool I saw in some other builders logs. Used it today to true up the edges on the H/S ribs, although they didn't need much. Also fluted them so they lay flat.

In addition to all the ribs, I worked on the fwd spar assy and got most of the way through it. Was worried about trimming away too much in a couple of areas and running into an edge distance problem like I've seen on a couple of other build logs, so I left plenty of extra where I could, and will trim it up for final assembly after everything is match drilled together. Will cleo the skeleton together next time, then final trim the center section.

  Oct 18, 2019     prepped HS aft spar - (3 hours)       Category: Empennage

Ended up with a bunch of other stuff to do today, so I only had a couple of hours to work on this. Match drilled the 609pp bars to the 603pp channels, including the #21 holes common to the HS708 ribs. I've got enough tools to start a Home Depot, but I couldn't find a #21 drill bit in my stash, so I ran down to the yard store and picked up a couple.

Located and match drilled all the elevator hinges including the VA-146 center bearing Assy. Was going to prime the bearing and the raw hole edges of all the steel brackets, but discovered that the rattle can of zinc chromate I have is clogged to the point of no return. I got it from the guys I bought the kit from and was planning to use it up and then switch over to zinc phosphate anyway, so its not that big a deal other than I cant really rivet together the VA-146 until I pickup some primer.

  Oct 17, 2019     H/S - (2 hours)       Category: Empennage

Worked a couple of hours on the new H/S this morning. Inventoried everything, shimmed my two shop tables so they would sit level end to end, radiused the ends of the aft spar doublers, broke the edges, & clecoed everything together. Realized that I didn't have a #12 or #21 drill bit, so I ran down to the yard store and picked those up before going to KBEC for a flight this afternoon.

I don't have to work tomorrow, so I'm planning to knock out the prep work and get this thing ready for primer.

  Oct 09, 2019     Rudder & V/S conformity wrap-up - (3 hours)       Category: Empennage

Cleaned all the old tape residue off the rudder & V/S and gave them one more look for conformity to print. Some of the -4 rivet tails on the V/S aft spar look a little tall so I put a gauge on them and discovered that the tails are all pretty much the correct diameter, but still little taller than I would expect. I think that the original guys could have gone with a 1/2 size shorter here, but none of them appear to be overly clenched, so I'm leaving well enough alone. Found one more skin rivet on one of the end ribs that didn't have the tail set properly and corrected that. The -3's don't seem to work or age harden very much and even though all the previous work on this kit was years ago, I was able to hit it again with a hand squeeze without the tail cracking.

The hinge points on the rudder & elevator are just heim joints. On the rudder, they had been screwed in, but not adjusted or torqued, and I spent WAY longer than expected obsessing over this. I found a few nicks on the bearing housings where I'm assuming the previous guys had screwed them in with pliers or an open end wrench, but nothing significant on the face of the bearings, so no damage done. I already had a tool for screwing these in which I made by squashing the end of a 1" pvc pipe into an oval to slip over the bearing end, and that's what I used for adjusting them in/out.

The print calls out a dimension from the center of the bearing to the face of the spar web. The bottom one is 1 1/16" but the other two are 59/64" & 51/64". Eyeballing a measurement to the center of a bearing down to 1/64" was challenging, but I want buttery smooth flight control movement so I spent a couple of hours measuring, running plumb line through the bearings, measuring again, etc. I finally got them to a point where I'm happy, and torqued down the jamb nuts. Vans doesn't call out a torque for the jamb nuts so I went with the 43.13 callout for shear nuts. The heim joints are 2 different sizes, so I went with 110 in/lbs on the -6 (bottom) and 80 in/lbs on the -5 (center & top).

At this point, the rudder & V/S are done, although I haven't hung the rudder on the V/S yet, so I'm hoping the hinge brackets on the V/S are true and it will swing freely.

  Oct 04, 2019     tested trim / torqued jamb nuts. - (3 hours)       Category: Empennage

After dialing in the fit on the elevator trim access panel yesterday, it occurred to me that maybe I should check to see if the servo worked, so I ran it back and forth with a 9v battery. All is well, but due to the way the jackscrew moves aft into a hole in the spar at the end of its throw, if the motor ever fails in any kind of nose up condition, I'm going to have a heck of a time getting it out of the elevator. fingers crossed!

I also torqued down the jamb nuts on the elevator hinge bearings. The print has a min/max measurement of 13/16-7/8 from the centerline of the bearing to the spar face. I measured them and they were at 7/8 exactly. I spent a while making a PVC wrench because I was going to crank them in a 1/2 turn or so, but then I realized that the hole in the center bell crank has already been drilled, so that's where they're staying.

  Oct 03, 2019     Elevator trim cover panel - (2 hours)       Category: Empennage

This was all assembled by the previous guys, but the nut plate rivets were proud and the cover panel didn't sit down right. I drilled all the nut plates out and saw that the rattle can primer they had used was pretty thick down in the countersinks. Cleaned the holes out by twirling a countersink by hand in there and took out maybe another thousandth or so. Also cleaned out the dimples that the cover nests into.

The lip on the nut plates stuck out into the hole and made it impossible to get the servo in there, so the other day I had ground off the edge of a couple of them. It was still a hassle and you had to clock the servo just right to get it past the rest of them, so before I took the nut plates out I marked the lip that was sticking out on each of them with a sharpie, then after I removed them, I removed some material up to the sharpie marks on the belt sander. They're steel nut plates, so I hit the raw edge with some zinc chromate primer on the end of a q-tip afterward. I gave the nut plate countersinks & dimples the same treatment where I had dressed the holes.

Put everything back together & it all fits a lot better now, but I didn't put the screws in yet. There are a couple of other things I'm going to need to do to the elevators before I call them done.

  Sep 26, 2019     set missing rivets & trial fit of trim servo - (2 hours)       Category: Empennage

Both elevators had rivets missing on the T.E. They had never been set because it's so tight in there. I was able to grind down a no-hole yoke and get them set with no drama.

The trim servo had already been mounted to the closeout plate, but the edges of the nut plates stuck out far enough that it wouldn't fit in the hole. I ground about 1/32" off the side of two nut plates and that was enough to squeeze it past them. The closeout plate isn't laying flat with the surrounding skin because the nut plate rivets are proud. Haven't decided yet if I'll shave these or what.

  Sep 25, 2019     wrong rivets in rudder - (.5 hour)       Category: Empennage

The rudder trailing edge top rib gets so tight that it's hard to get a bucking bar or squeezer in the aft most position. Because of this, Vans calls out a MK-319-BS pop rivet as an alternate to a driven rivet in this location. When the previous owners built the rudder, for whatever reason, they used the wrong rivets in here. Instead of countersunk, they had just pan head pop rivets.

I drilled these out assuming that I was going to have to dimple via a male die on top of a countersink in a 3/8" steel plate slipped in there, but to my surprise, the pan heads was installed over a dimple. Once they were removed, the proper rivet dropped right in with no problems at all. This has been the easiest thing on this project so far.

Don't have any idea why they used the wrong rivet. There were plenty of the correct ones in one of the hardware trays that I got with the kit. After discovering this, I looked over the rest of the rudder in detail. Not only for build quality, but also for conformity to print. This was the only area I found where they went "off plan"

  Sep 25, 2019     redo-decision - (6 hours)       Category: Empennage

I'm doing several entries on 09-25, but they represent work that has taken place in little bursts over about the past week. I drilled out the remainder of the aft spar reinforcing bars without incident, but, while I was in there I decided to do the FWD spar doubler reinforcement SB. Was using my new rivet removal tool that's supposed to center the drill bit, but somehow I got off to one side and beat up the R/H fwd HS spar before I realized that it wasn't centered. It's not all the way through, but a -5 rivet won't clean it up. The word from vans is that if a -5 doesn't do the trick, that I should probably replace that spar. I unskinned the R/H of the HS & drilled the ribs apart in preparation for that & then took a couple of days to ponder how I wanted to proceed.

Ultimately decided that reusing flight critical parts like the spar reinforcing flanges etc. isn't worth it to me, and I'm not sure I 100% believe that new skins will fit the old ribs (ribs are cheap) so I think I'll just build a new H/S.

  Sep 17, 2019     continue disassembly of L/H horizontal stab. - (4 hours)       Category: Empennage

Removed all the skin to substructure rivet tails & drilled the heads off the 609PP aft spar doubler bars. These are long -4 rivets and even with the heads snapped off they don't want to come out. Did a pilot hole for the rivet removal tool with a small bit and then after the heads were popped I went back with the same small bit and drilled most of the way through the rivet shaft so the shafts can collapse in on themselves. I then drilled a hole in a hardwood block slightly larger than the rivet tails and used it to back up the structure. Used a pin punch smaller than the hole to knock the tails out. RJ was studying for math, but took a break to hold the backing block for me. Thanks RJ! Only did about a dozen because I bent the el-cheapo pin punch, but will get the rest tomorrow.

  Sep 16, 2019     Re-skinning H/S - (3 hours)       Category: Empennage

I drilled off the L/H horizontal stab skin due to that double drilled hole that the previous owner gifted me with. Didn't have any obvious blow outs of any of the sub-structure, so I went ahead and ordered a new skin, aft spar & the service bulletin for the main spar doubler. To save on shipping, I also ordered some hardware & the sb for the elevator hinges and the inbd aileron hinge doubler. That stuff should all show up early next week.

I still need to drill apart the aft spar doublers on the L/H side. I'm hoping I can reuse them. I'll put a gauge on all the holes after it's apart just to confirm that the holes are still in spec.

The Horizontal stab is one of the first things built, so I'd expect it to have the lowest build quality. I looked at it pretty closely as I was taking it apart and I cant see any major defects with what they've done. All the internal structure was primed and the rivet tails appeared within spec. Makes me feel pretty good about the rest of their build quality.

  Sep 12, 2019     disposition from Vans Category: Empennage

Got an email back from Sterling Langrell at Vans Tech Support re. what to do with the double drilled aft spar & the flanges on the main spar.

"Match drilling a new skin to a once completed structure is okay but the holes are accurately punched enough we recommend just reaming the holes in the skin and it will match the underlying structure.

The flanges that remain on the spars are not a problem, you can flatten them with a smooth faced hammer and remove the curve."

I'm going to take him at his word that the prepunched design is accurate enough that I can have a new skin fit old ribs. Tomorrow I'll drill off the old skin and the left aft spar, then order new parts. I'll wait until I get the old stuff removed before placing the order, so that if I blow out a rivet hole and need to order a new rib or something I can catch it on the same order.

  Sep 11, 2019     Research/double drilled hole & SB - (2 hours)       Category: Empennage

Left HS upper trailing edge, 11th rivet outbd. Looks like the dimpler got away from the original builders and they punched an extra hole in the skin here. Their solution was to drill and dimple the aft spar flange here and install a rivet in both holes. Not only does it look goofy, there's no way I have min. pitch between rivets, although I think I'm good on distance to the radius of the spar flange. I suspect that the skin will eventually crack between these two rivets.

My initial reaction is to replace that skin as well as that half of the aft HS spar, especially since I'll have to drill out the root ribs to comply with the elevator service bulletin anyway, but I don't know how much of a problem it will be to match up a new match drilled but undimpled skin to the existing dimpled ribs. I emailed Vans to see what their builder support guys thought and haven't gotten a reply yet. If they say "use as is, no problem" I'm going to have to think long and hard about whether to go that route and save myself some work or drill it all apart and fix it just because I don't like the way it looks.

SB14-01-31 Installs some doublers behind the center section of the main HS spar to deal with potential cracking from the relief holes at the corners of the spar where the flange has been removed in the center section. I'm definitely doing this while I've got the H/S laying on a bench unpainted. When the Original guys removed the center spar flanges per print, they didn't completely get rid of them. There's still about 1/4" of flange inbd of the relief hole for a distance of about 3/4". I don't think it will hurt anything, so I'll likely leave it unless it interferes with the doubler plates or Van's tells me that it's a problem for some other reason. Since I was already reaching out to them re the other issue, I asked them about that as well.

Here's a cut and paste of part of the email that I sent to them on 9-10-19. Waiting for a response before I ordered the SB kit, to decide if I want to order a new skin and left rear spar at the same time and save myself some shipping $.

The dimpler got away from them and punched a hole through the upper skin near the 11th AN426AD3-3.5 rivet out from the inbd end on the LH trailing edge. Their solution was to drill & dimple both holes and install two rivets in that location. Both rivets go through the skin & HS-603PP. Rivet pitch is only about 7/32��and the mistake rivet is 1/4��aft of the upper flange radius for the HS-603PP. I think I'm good on the distance from the radius, but nowhere near good enough on rivet pitch (is it supposed to be 3d minimum?).

Questions:
1. Use as is?
2. Put a doubler behind the spar web
3. It looks pretty micky mouse, and I imagine it will crack sooner or later, so my inclination is to order a new skin & left HS-603PP, and reskin it. I understand I might scrap some parts if I oversize holes, but assuming I don't, what sort of problems am I likely to face match drilling a new skin to dimpled ribs? I don't have a problem ordering new LH ribs as well if that stands a better chance of getting a descent fit.

Issue 2:

I would like to go ahead and comply with SB14-01-31. Looking at the HS-702 inbd end, the flanges haven't been completely removed per HS-702 Front Spar Tab Detail. A partial flange extends about 22/32��inbd from the 1/4��relief hole at all 4 locations.

Question:
1. Will these flanges interfere with the SB plates or otherwise cause a problem? I'm inclined to leave them alone unless you tell me I need to remove them.