Sep 14, 2022     main power wire bundle permanently routed - (6 hours)       Category: Firewall

Finished the firewall passthrough for the main power wire bundle. The instructions that come with the firewall passthrough I got from Spruce have you wrap the wire bundle in fire barrier cloth burrito style, then wrap that in silicone tape, stuff it in the tube, then tighten it down with worm clamps. I followed the instructions, but wasn't happy with the result. Seems to me that would let smoke and engine fumes find their way through the burrito into the cabin.

With that in mind, I undid it all, then modified the installation to recess the burrito into the tube about 1/4". This way the next time I crack open a tube of fire barrier I can fill the passthrough tube for a nice airtight fireproof plug.

This bundle contains the 8 awg wire to the main BUSS, as well as the shunt wires for the ammeter, and the wires from panel switches to the batt and start contactors. With that many amps running through there, I want to take the utmost precautions against chafing and shorts, so I wrapped the entire thing in Nomex split wire sleeve.

I got this stuff surplus at the yard store a while back. It's the same product that I've seen in the gear wells of some big airplanes, as well as all over helicopters. It's really tough stuff, and also won't support a flame.

Secured the bundle to the engine mount with hi temp adel clamps in such a way that it won't be able to rub on anything and will also be out of the way for ongoing servicing and future maintenance.

I also played around with several different possible solutions for blade fuses on the ammeter shunt wires, but in the end, the simplest and neatest solution I could think of was just to use two screw together type in-line fuse holders utilizing 1 amp glass fuses

I'm not a big fan of glass fuses. The small ones especially have such tiny filaments that they are sometimes prone to vibration induced failure. But in this case, it one fails the only thing that will happen is that eh ammeter will quit working. If it becomes a problem, I'll come back to this and reconsider something more complicated utilizing blade fuses, but for now this seems like a simple and tidy solution.

  Sep 13, 2022     firewall fwd work - (8 hours)       Category: Firewall

last night Kriya helped me shoot on the firewall recess after I sealed up the flanges with 3M fire barrier, then I ran a bead in the gaps.

I let it dry overnight and then today reinstalled the battery box, and a couple of things that I'd removed on the cabin side for access. Installed the second ANR 60 amp fuse that finally came in from B&C on backorder.

Also added nut plates to the lower flange of the firewall. The plans are pretty bare of details here, but I elected to go with 4 evenly spaced #8 nut plates on each lower flange for attaching the cowl, and 4 additional nut plated in the center area for future installation of an outlet ramp a la Dan Horton to increase exit air velocity and reduce turbulence of the cooling air in the lower cowling.

Permanently installed the engine mount by torquing all -6 bolts/castle nuts to 160-190 inch lbs and installing cotter pins.

Started installing adel clamps for battery cables etc.

  Aug 03, 2022     extra wiring passthrough - (1 hour)       Category: Firewall

way back in the day, I had installed wiring passthroughs on both the left and right top corners of the firewall. I reasoned that I would use the one over the battery for all power and the one on the port side for all signal, p-leads etc.

Unfortunately, I didn't think to check my avionics plan to see where the wire bundles were designed to position all the boxes. What I'm left with is a situation where all the signal wires also need to come out the starboard side. I discussed this with various people and the general consensus was that I could probably run them all through the same hole without interference, but I'd be a test case because nobody does it that way.

I originally thought that I'd give it a try, with the understanding that I might have to undo some stuff if the engine instrumentation got wonky every time I pulled a few more amps through that main power wire into the main buss.

Ultimately I chickened out. The thought of having a major wiring redo and poking more firewall holes after I get into flight test was just cringe worthy, so I went ahead and installed another passthrough on the starboard side.

The plan will be for all power wires to go through one of these, and all sensor wires going through the other. The one on the port side will end up only having P-mag wiring and maybe a few spare wires for future use shoved through it. Wish I would have defined this better early on. Clearly, two would have been plenty if they were just in the right spot.

  Apr 02, 2022     Firewall odds and ends - (5 hours)       Category: Firewall

This entry is for work completed yesterday.

Started the morning by installing the firewall passthroughs that I got from ACS. (FYI- I saw thet several people on VAF have used stainless shower rod holders from amazon to fulfill this same purpose, but I think that's somewhat questionable from a QC standpoint, so I sprung for the real ones. Not cheap, but they also came with everything to complete the installation. clamps, hardware etc. which was nice.

Anyway, you'll notice that these are not symmetrical. Thats to give lots of knuckle space from the brake master cylinder on the starboard side and from the future oil cooler duct on the port side.

They installation of these is pretty straight forward, but they require a 1 1/8" hole. I don't have a chassis press nor am I going to buy one for two holes. I drilled these with a 1" unibit. The firewall is only about .017 thick, so by the time you get up to a hole that big, the bit is chattering a little, and it also actually radiuses a flange on the inside of the hole as it pokes through.

I have a unibit that goes bigger, but didn't see a need to use it. once I got to 1", I got out the dotco with a new rotary file and cleaned up the radius & it was almost perfect.

Before snugging this all down, I sealed the mounting flanges with flame master 1000. I'm making that little tube that came with the heater valve go a long way!

Task two was to figure out how to insulate the battery positive lead where it goes into the master contactor. Then issue here is that this wire is always hot, and it's capable of dumping a lot of amps if something shorts it to the firewall. I know a lot of guys who don't worry about it since it's pretty well hidden under the battery, and they are convinced that good shop practice will keep them from ever having a problem.

Honestly, they're probably right, but if I dig 30 years deep into the sock drawer, I can show you a melted spot on my high school class ring (which I was wearing at the time) that illustrates pretty clearly that it's a good idea to cap those battery cables.

Anyway, the issue that needs to be overcome is that standard boots are pretty much all designed for a straight terminal lug, but the layout of everything in the RV7 requires a 90* lug. To fit properly, the boot needs to be an "S" shape, not an "L" shape.

After playing around with this for a while, my solution was to cut up two boots and use them together, with the top one being wire tied to the terminal lug so it's not going anywhere.

Located and installed the ammeter shunt. There are two schools of thought on where this should connect. If you put it on the B lead, it will show alternator output. if you put it downstream of the battery contactor it will show the total load. of everything you have turned on.

Option 2 is what I'm used to, so thats how I installed this one.

Note there's no cover on this as received from garmin, but it's only hot when the master is on. I can't imagine why I would ever be under the hood with the master on, so I may or may not craft a cover for this at some point.

I was planning to mount the shunt via some #8 screws into nut plates, but the mounting holes are 3/16 and the fwd side of the base is milled to capture the heads of AN3 bolts, so it was easier to just poke a couple of bolts in there and use fiber lock nuts from the cabin side.

The final detail of the day was to go to Ace and get some stainless lock washers and and better nuts. I put a split washer next to the firewall on the ground stud, as well as on the Blue Sea ANL holders. At this point I'm feeling pretty good about the robustness of my main ship electrical architecture.

  Mar 31, 2022     Battery Cables + Forest of tabs - (8 hours)       Category: Firewall

manufactured both battery cables out of 2 gauge welding wire, with ring terminals swaged on with my nifty new molex big cable crimper. This is the only aircraft tool I've ever seen where the instructions have you hit the tool with a 2 lb hammer in normal operations :)

I wanted to make the positive cable as short as possible and had originally made one about 10" long. Welding cable is so flexible, I though I could make the bends around the battery box and possibly use one of the battery box mounting bolts to anchor an adel clamp to.

Unfortunately, I could see a potential for the cable to rub on the corners of the box even with a clamp. The radius is just too tight. So, I scrapped that plan.

Fortunately, I had bought a couple of feet of wire, as well as some extra terminals, so I had enough extra for a second attempt.

This one is 12" long, and is well away from the battery box top and bottom. I'll eventually install an adel clamp to a nutplate on the firewall about midspan, but I the correct size adel clamps are on backorder at Airparts and won't be here until next week, so there's no rush with that.

For the negative cable, Vans OP-30 has you upsize the second rivet hole down from the top starboard side of the firewall cutout for a -4 bolt and attach the ground there. With all my fancy avionics, I'm going with the forest of tabs that everybody uses. I'm putting it in a common location, centered between the F-7108 center fuselage rib and the F-7107-r right fuselage rib, and 2.5" up from the angle that runs across the firewall at the top edge of the cutout.

Based on that, I turned Vans original location into a mount point for a adel clamp by installing a #8 nutplate in that location.

The forest of tabs that I got from SteinAir comes with a big brass bolt to use as a mount point. It goes through the tab, through the firewall, then a washer and jamb nut, then a washer, battery cable, another washer, and then the main nut.

Couple of issues with this;
Issue 1- It has a hole in the middle for another mounting screw, but I elected to not just have the whole other half of it hanging, so I drilled and installed a -3 nutplate on the other end for an AN3 bolt. Now its secured by a 5/16" brass bolt on one end and an AN3 bolt into a nutplate on the other. It's overkill from a structural standpoint, but it's about the best electrical connectivity back to airframe ground I can figure out how to implement. I think that Vans design just has an airframe ground to the aforementioned AN4 bolt and a ground strap from the engine to the firewall, but I think I'll likely run a ground cable from somewhere in the general vicinity of the starter back to the battery or to the firewall side of the brass bolt as well, so that pretty much everything will have a copper wire ground path back to BATT negative rather than running through the airframe. Hopefully that will encourage all the electrons to play nice and eliminate the potential for gremlins in the engine sensors.

Issue 2- If you look at the stackup on the brass bolt that I listed above, you'll notice that there's no locking device whatsoever. Yeah, the bolt it clamped to the forest of tabs and the firewall with a nut, and yeah, there's another nut on top of it, but it anything works loose in that stackup, I could start having intermittent or weak ground issues with all the avionics, and main ships power as well. Not as catastrophic, but certainly annoying, if I ever have to take this thing apart after the plane is finished, it seems likely that the bolt could just start spinning in the hole before the top bolt comes loose.

I believe this stackup needs a split lock washer under the first nut, squeezing on the firewall. however, I don't have one in the correct size right now, so I'll have to acquire one. or maybe two. I'll ponder this for a while.

I also wanted to do a little more under the panel before I started pulling wires, so I played around with routing for the heater cable. This led to discovering Van's OP-26 that shows where to drill a hole through the firewall stiffener etc. I accomplished this, then started thinking about how to run wires through the tunnel and up the cabin side of the firewall.

This led to needing to install the heater diffuser cover in the cabin to visualize things, which led to temporarily installing the firewall recess, which led to installing a couple of nut plates in the recess to attach the cover to later...you get the idea.

  Mar 30, 2022     contactor diodes & first cable crimp - (8 hours)       Category: Firewall

Somehow I ended up with two starter contactor diodes and zero master contactor diodes. General consensus is that these are probably identical, but that it's likely that the reason that VAN's color codes them is that the big terminal and little terminal are on opposite ends i.e. the diode orientation is opposite depending on what contactor it's going on. These pre-made units don't have enough extra length to cut the terminals off and put the correct ones on either.

I had an extra batt contactor with diodes already installed. It's a B&C specialty 4 post that I had gotten in a box of switches and stuff that I bought from VAF. I had originally decided not to use it because since it's use dit didn't come with any instructions and I couldn't get my mind wrapped around if the diode and jumper were on the right terminals. But, last night I was able to find a wiring diagram on the B&S website and was able to confirm that everything was on the right post.

I swapped it out with the 3 post that I had originally installed, but then discovered that evidently the mounting tabs are in a slightly different location and the copper strap that goes between the two contractors was now about 1/16" to short.

I played around with the idea of oblonging some holes, but ultimately decided to just make another copper jumper in the correct dimension.

After that was done, I drove up to Newton and picked up the welding cable, ring terminals & battery cable crimper that I had ordered from B&C. I also swung by Airparts and picked up some nut plates and steel fuel and brake line fittings for the firewall so I can replace the aluminum ones that Vans provides. That's one great thing about living in Wichita. Most aviation tooling and hardware isn't more than 1/2 hour drive from home if you know who to call.

When I got home, I played around with the my new toys and crimped one end on the welding/battery cable. The crimper is they style that you hit with a hammer to make the crimp. I sprung for the aviation specific one from B&C instead of the generic one from the big box stores because it has a depth gauge to make sure that you don't overcrimp. However, it has one side offset, presumably so that if you're squeezing a two-wing terminal it will fold one side over the other. When you're crimping a terminal with a solid one piece tube for the wire to go in, it results in one side being slightly larger than the other. I only mention it because you can see it in the picture below and it looks kind of goofy, but it's supposed to be the way.

In a day or two, I hope to have the firewall fwd electrical architecture done and move to the other side of the firewall!

I capped off the day by changing a garbage disposal in the downstairs bar sink, and for good measure, discovered a leak in the discharge line from the associated dishwasher. Nobody ever uses that sink or dishwasher, and much like an airplane, the worst thing you can do for home plumbing is to not use it :(

  Mar 27, 2022     oil cooler - (8 hours)       Category: Firewall

Now that the parking brake valve is squared away, I went on the other side of the firewall and riveted on the oil cooler plenum.

I didn't have a flush set that was long enough to get in the tight area on the vertical flanges where the plenum is several inches deep, so I elected to just go simple and used AN470 pan head rivets.

Behind the round flange where the scat tubing attaches clearance was tight, so I reversed those two rivets and was able to buck the shops heads on the fwd side with a bucking bar that has an angle on one end for just this kind of thing.

The cabin heat valve came with a small tube of flame master 1000 (red RTV), so I went ahead and permanently attached the heater flapper and used some of the extra in the tube to seal up the corners of the plenum.

Also fiddled with a few other things and burned up the rest of my shop time, but nothing very noteworthy

  Mar 23, 2022     Contactors and ANL fuses - (4 hours)       Category: Firewall

Permanently installed the Batt & Master contactors. It's hard to see the connections but basically, the two contactors are connected via 2 copper straps per print. Then another strap jumpers to the top ANL base and then another one goes down to the second ANL base. All of the copper straps are covered in a double layer of heat shrink insulation, because once you hit that master switch, them and the Batt positive cable (yet to be fabricated) are pretty much the only unfused items on the airplane, and I have no intention of just having bare copper hanging out in the breeze.

The idea is that the starboard side of the top ANL will feed the fat wire going into the cabin breakers and the bottom one will carry the output from the alternator back into the system.

This is a common setup and anticipates the two most catastrophic failure modes; 1- a short in the fat wire into the cabin 2- a failed diode in the alternator that causes it to shove beaucoup amps into the poor electrical system.

  Mar 22, 2022     Contactors & battery box - (6 hours)       Category: Firewall

The lightweight battery box from EarthX for the 680c has the mounting flanges pre-drilled. Because this box is smaller than the one vans originally intended, it wasn't wide enough to pick up an existing rivet on the starboard firewall diagonal brace, so a while back I had extended that flange. Unfortunately, once I laid out the contactors per print, I discovered that the plastic bottom of the battery was almost rubbing on the crown of the Batt contactor.

Teh easiest thing to do to fix tis seemed to be raising the battery, so I cut both flanges off the battery box and made new ones out of some angle &/or .063 scrap. relocated the battery box about 1/4" higher and now all is well.

I also wasn't happy with the battery retention solution on that box. Basically just a tab bent over on the front that caught the lip of the battery. I don't have any doubt that it would hold the battery in the box, but flexing that tab forward and lifting the battery out while standing on my head over the back of the engine seems less than fun, so I cut that tab off as well and fabricated a conventional strap arrangement. I'm rapidly running out of the .063 scrap that I had left over from cutting up the instrument panel, but I've put it to good use!

The EarthX 680c battery comes with foam inserts in the box to take up space in the bigger battery box, and I used some of them to pad the bottom flanger that the battery sits on as well as the new top strap, and now the battery is nice and snug. look good, last long time.

  Mar 21, 2022     Batt and Starter contractors + fuel passthru - (4 hours)       Category: Firewall

Well, I talked to Kevin at Vans Builder Support this morning, and the gist of the conversation was that I was trying to solve for a problem that doesn't exist. i.e. the engineering is correct, and that teeny rivet pitch above the start contactor is per Engineering.

The 3 most obvious choices are 1-build per print, 2- skip the nutplate and just use a fiber lock nut on the cabin side, 3- lower the contactor enough to drill the next lower rivet hole 0.25 for a bolt and then center the nutplate on that. Kevin confirmed that any of those options are fine.

I originally though I would go with option 2, but the more I thought about how much it would suck to be stuck on the road somewhere and not be able to swap out this $15 part without a second person, the more I didn't like that idea. Eventually I went with Vans engineering. you may be able to see in the photo, but I went with an oops rivet in this location just for convenience of not having to countersink the firewall so deep.

Turns out that when I got to looking this, the starboard most nutplate for the BATT contactor has the same thing going on, as does the fuel line doubler (just with rivet, not a nutplate)

Long story short, I installed the contactor nut plates per print, but elected to make the fuel doubler 5/8" taller which allowed me to pick up a second existing rivet in the firewall & vertical member rather than having yet another rivet with ridiculously small pitch. I also made it about 3/8 wider. These two things allowed me to move the fuel fitting penetration both laterally and vertically about 3/8" to relieve the otherwise uncomfortably close proximity to the hot lug of the start contactor that everybody warns you about.

Like a lot of things on this project, this seemed like such a simple operation, but ended up taking way more time than expected.

Anyway, it's all done now and came out okay

  Mar 19, 2022     Started BATT & Start contactor install - (2 hours)       Category: Firewall

On the surface, this seems pretty straightforward, but I ran into a problem about 1/2 way through that I wanted to ponder before I got drill happy.

Per print, you're supposed to locate the most inboard nutplate for the start contactor by drilling out an existing firewall rivet and using that hole for the lower leg, then match drilling the upper nutplate leg. This would result in WAY below normal min rivet pitch with the existing firewall rivet immediately above.

I drilled the rivet out for the lower leg, then when I saw how close that big nutplate was going to be, I got the ruler out. If I drill the hole for the upper leg per print, it will only be about 7/32" or .2185". I dug out the mil-spec for this, and min pitch between two countersunk rivets is #3 rivets is .438" so basically half.

I get that manufacturer engineering takes precedence over generic mil-spec guidance, but this just doesn't seem right. I looked at a lot of build log pictures online and a bunch of people just drive ahead here and live with the sub-standard rivet spacing, but I've never seen where anybody talked to Vans about it.

I'm inclined to skip this nutplate and use a fiber lock nut on the inside, but if I do that, I won't ever be able to change this contactor by myself because somebody will have to hold the head on the outside while somebody else turns the nut on the cabin side. Seems like a bummer, but really, how often do you have to change a starter contactor, maybe once every 5-10 years?

I may call vans on this on Monday, more out of curiosity than anything.

  Mar 05, 2022     Oil cooler - (10 hours)       Category: Firewall

I logged 10 hours for this because I've spent at least that long figuring out where to put the darn thing.

Darwin Berry was kind enough to send me several pictures of his layout, but they didn't have measurements. When he did his, he did it with the engine on to make sure it didn't interfere with stuff. I counted rivets in teh photos and thought I could lay it out pretty close with just the engine mount on, but the idea of getting off just a little and having a clearance problem with the back of the engine made me hesitate to drill the holes, even with the engine unwrapped and available to measure.

Seemed like without precise measurements, I was doomed to wait until the engine was mounted and work around it just to be safe, but then I remembered that Steven Christoper had done a similar installation, so I called him to see if he by chance had exact measurements for his installation.

He didn't but as luck would have it his engine was off for an overhaul, so he was kind enough to go out to his hangar the next day and take measurements.

I installed to engine mount just to be sure, then laid it out duplicating what he did on his airplane. Looks like it will work fine there so I went ahead and drilled it to the firewall. I'll know in a couple of months when I hang the engine if that was a blunder, but as of now I'm happy to have that out of the way

FYI- I absolutely wouldn't try this without the engine mount on, measurements or not. I think that theres enough variation in the engine mounts and other tolerances that would be a dicey proposition. I laid mine out exactly per Stephen Christophers great measurements, and there was practically zero clearance with the lower outboard corner of the oil cooler and the engine mount tube that runs through there. I moved the assembly inbd about 1/8" for peace of mind.

WARNING- Future self says if you're going to do this, do yourself a favor and drop the plenum another 1/2" or so. In my case, this was tight enough to the engine mount tube that runs right above it that I wasn't able to clock a 90 inboard from the outboard oil cooler port.

I screwed around with this a bunch mocking up different hose routing, but finally came up with a solution that will work. would have been a lot easier if Could have just clocked a 90 inboard.

for details, look at my engine entries starting around December 2022.

  Mar 02, 2022     more firewall stuff - (24 hours)       Category: Firewall

Over the last 3 days I finalized my power distribution plan and ordered a bunch of stuff from Stein. That took probably 5-6 hours of careful measuring and panel layout to make sure the vision would actually work.

In the shop, I knocked out a bunch of stuff. I located and installed the brake master cylinder, The main ship battery box, the cabin heater valve, and trimmed the lower corners of the firewall for the landing gear legs.

The master cylinder and heater valve were located per print, but I'm off the reservation with the battery box since I'm using a small earthX battery. This took a lot of measuring and layout to make sure I wasn't creating conflicts and some on-off with the engine mount.

one of Vans prints has a battery box for an Odyssey 680 battery which picks up two holes through the firewall vertical support just right of the cutout, and one on the starboard diagonal firewall brace. Since this battery box is smaller, the spacing didn't work out, so I added a tab on the starboard flange of teh battery box to pick up an existing rivet hole in the diagonal brace. The print is very clear that there's only one -3 bolt on this side in vans installation, but I don't know if I like that arrangement for the EarthX box. Seems like it might be prone to flexing. I'm going to ponder this a little bit and I may come back to it and add another fastened or two on the starboard flange into a doubler on the cabin side.

The RV-10 oil cooler mount arrived a couple of days ago, so I spent some time riveting it together. I'm definitely on my own with locating this, as Vans has no engineering for this cooler on the RV7. Fortunately, a lot of guys have done this already, so I've been reviewing other build logs and corresponding with some guys regarding what they've done and I think I have a location that will work.

This will require precise location, because if I'm off just a little on the low side it will interfere with the main gear socket bolt on the bottom, or if it's too high, I won't be able to get the cooler line fittings on it. I'm also concerned that I'f I get it to far inbd, it might interfere with the left mag or wire harness or something.

Based on all this, I decided theres no substitute for just laying eyes on what I'm dealing with, so I spend a couple of hours unboxing the engine so I could check out where stuff sticks out on the back side.

My experience with engines back in the day; it would show up bolted to a steel cradle in a big crate, get unloaded with a fork lift, picked up with a cherry picker, and hung on the pylon on the back of a Citation. 2 guys, 1 shift, done.

This is a little different :) Lycoming preserves the engine, seals it in a plastic bag with desiccant indicators, then wraps it in another plastic bag, then fills the crate (cardboard box on a pallet) full of expanding foam. It took me, no joke, probably 2 hours to carefully cut the cardboard box off of it and pull all the spray foam off of it down to the level of the sump. I filled 2.5 lawn trash bags with chunks of foam and as I type this, my fingers are sore from breaking off chunks of foam.

After all that, I was pretty beat and decided to call it a night and pick this back up next time.

  Nov 21, 2020     FF-00098 tabs - (.3 hour)       Category: Firewall

Had a few minutes this morning so I ran out to the shop and match drilled these tabs per print and build instructions. This finished all the tasks in that section of the build instructions. Feels good to be able to check that off.

  Nov 20, 2020     Firewall - (5 hours)       Category: Firewall

For some reason, I was really paranoid about messing this up. I must have measures, clamped, unclamped adjusted, and reclaimed a dozen times. Also had to shorted one of the longerons another 1/16" or so to get the firewall to nest appropriately on one side because the firewall weldment was hitting the longeron before it was located per print. It was such a small amount that I didn't want to hack at it with a grinder, so I knocked it down with a vixen file.

Note- The print says that the AFT side of the firewall should be 5/8" aft of the leading edge of the F-770 skins. The instructions give that same measurement from the FORWARD edge of the firewall.

I figure that it's going to be pretty much impossible to accurately measure this to within a .020 or whatever the firewall thickness is anyway, so I elected to get it as close as possible using the fwd dimension, because it's easier to measure.

At any rate, I clamped this thing up with about a million cleco clamps and 3 sets of vice grips on each weldment. Walked away, had a cup of coffee. Came back, remeasured everything one more time. Then drilled in the sequence called out per instructions.

Came out fine, and only got cut once by stainless steel shavings :)

  Aug 13, 2020     Finished firewall - (5 hours)       Category: Firewall

Yesterday I squeezed all the perimeter rivets with a hand squeezer, then repositioned the firewall vertically by strapping a bungie cord to a 2x4 screwed vertically to a workbench. Shot the rest with rivet gun. Had a couple where the tails were goofed up due to juggling everything and 1 where I mistakenly used the wrong length rivet. Decided to call it a night.

This morning, I drilled out the goofs and reshot them.

I've read several builders logs where people have stated that the rivet callout in some areas was too short, but I didn't see that problem. What I did notice is that there are a few places where there are multiple layers stacked up, and particularly in the corners the stack up isn't constant. In all 4 corners there is 1 rivet that is a -7 where all the rest of them are -6's. I'd like to claim that's why a used a rivet that was too short in one hole, but the reality is that I was getting tired and just grabbed the wrong length.

In the photo, you can see what looks like scuffs on the F601 angle, but it's just where I put some tape on prior to riveting to protect the angle and when I peeled it off the next day a little primer came with it. Will touch up later.

  Aug 11, 2020     Primed all support structure, clecoed everything together - (3 hours)       Category: Firewall

Prepped everything and clecoed together. Nothing left on the firewall except riveting. I've seen a lot of build logs where guys have used a longeron squeeze around the edges and then back riveted all the field rivets. Seems to me that it would be just as easy to fwd rivet the field rivets with the firewall vertical. I'll give this some thought tonight.

  Aug 10, 2020     Firewall continued - (4 hours) Category: Firewall

De-burred all holes, dimpled firewall, countersunk support structure as required. Was raining today so I held off scuffing and priming until next time so I can prime outside. All firewall components done except for some sharp edges that need to be smoothed down.

  Aug 10, 2020     Firewall continued - (4 hours)       Category: Firewall

De-burred all holes, dimpled firewall, countersunk support structure as required. Was raining today so I held off scuffing and priming until next time so I can prime outside. All firewall components done except for some sharp edges that need to be smoothed down.

  Aug 02, 2020     match drilled firewall - (5 hours)       Category: Firewall

So on July 16th, I was clecoing up all the firewall parts in preparation for match drilling, when my cousin called and told me that Mom had fallen and broke a hip in Missouri.

I left that same day and was back there for a couple of weeks, and will continue to be back and forth for the foreseeable future.

Today, I got the opportunity to work in the garage for a few hours so I finished fabricating the F601 angles and the brake & fuel pump doublers. Match drilled everything.

I'm leaving again tomorrow, but when I come back all the firewall parts are ready for dimpling/countersinking.

  Jul 10, 2020     firewall layout - (4 hours)       Category: Firewall

found all the pieces for the firewall, read through the drawings and instructions a couple of times and started laying stuff out. In addition to the normal de-burring, a couple of the angles that brace the back side of the firewall needed to be trimmed to nest properly.

There are a couple of big pieces of angle that need to be cut out of .187 angle stock and about half way through, the band on my band saw broke. It's an old Craftsman that takes a 80" blade. I checked Lowes, Home Depot, Ace, even Grizzly Tools. The only ones that are available here locally in that size are for wood. I ordered a metal cutting blade from Home Depot and it's supposed to be here in about a week.

I finished off those angles with a hack saw, but am just not happy with how they turned out. By the time I got the hack saw marks filed out of the cut edges I've got the bare minimum ED on one of them and since the lower center engine mount bolts eventually go through them I think I'll sleep better if I remake them.