02/22/2009 (6 hours):
I didn't get as far as I'd hoped today, but I did make good progress. I got a late start because I stopped by the hardware store to pick up some things I figured I needed, then discovered I already had. Oh well.
My layup of the final UNI wraps was still not completely cured, but it was good enough to start working on, and hopefully the 6 hours at 70+ degrees today, plus the leftover heat in the hangar, will finish the job tonight. It was slightly tacky as I cut the excess off, so I didn't do a full trim - just got it pretty close with the Fein, and I'll finish it off later.
I got a workbench set up with a sheet of plywood against it, and leveled out. The hangar floor was actually remarkably close to level, at least in that spot, which saved some time. I had to trim the built-up trailing edges because I made them slightly over-sized, but heck, that's why I made them slightly oversized. I discovered two miscalculations here:
1. My built-up trailing edge shapes are not identical. One is slightly thinner than the other. I presume this is because this section is shaped by hand/eye - they ARE the same length. I think I just have a low area where I over-sanded one, and I'll have to add a bit of micro here when finishing. Not the end of the world.
2. Second, one brake line tube doesn't run all the way up to the end where I trimmed it. I'll have to drill around in there a bit (I think it's about 1/4" in) to find it. Also no big deal.
Trimming the gear leg was easier than I expected, given all that others make of this. I used a fresh hacksaw blade on each leg, which definitely helped, but it went along fine. I then set the leg against the plywood, did all the marking and measurements called for, and built up the support box.
This all took about 6 hours, and I was planning on making a full day/evening of it and doing the attach tab layups, but I had to stop for the day. When I set up my only spare worktable I discovered it was bowing in the middle, clearly not strong/stiff enough to support the gear. (It's not the main bench - that's in use right now.) I'll get a solid-core door from the Borg next trip out and pick up where I left off.
03/05/2009 (6.5 hours):
I found a table I wasn't using in the corner of the shop, cleaned it up a bit, and pressed it into service. It took a lot of fiddling to get everything leveled properly and I was still off about 1/16" where the trailing edges were supposed to fall on the same line. I finally figured out that I had a bit more material at that point left over from the trimming. Phew!
Laying up the attach tabs was actually a pretty straightforward step - time-consuming, but not hard. I followed the plans pretty much verbatim, except I used duct tape to seal off the box because box sealing tape is just not sticky enough (on wood). Other than that, it was a long layup but not particularly hard. Others have had to squeeze the heck out of their tabs with clamps to make sure they aren't too wide - I didn't have to. According to the plans M drawings (and some math) they can be up to 7" wide. Mine were 6.75" wide, so I just applied light pressure to produce a very flat surface. Hopefully this will be correct in the end!
03/08/2009 (8 hours):
I've learned something over the years as I've worked on the Cozy. A "step" really has no meaning in terms of time. There's no average length of time that one takes, nor is it even a good marker of logically separate tasks. Some steps take an hour, some steps take 6 days. Sometimes one paragraph can mean a huge amount of work, while other times four paragraphs is just a small job. This is a big one.
Today I got an early start, and it was a good thing I did because the next "piece" of this step took all day. I drilled the attach tab holes per plans, and with very minimal tweaking was able to get the drill bit to sit smoothly in the holes with no play. I then removed the box from the gear leg, and spent well over an hour chipping and chiseling bondo and bits of wood out of the attach tab areas.
Once I got all that cleaned up, I prepped the area for layup, did the flox corners, and installed the UNI and BID plies on the inner surfaces. That went a lot faster because John wet out the BID while I installed the UNI. It's a good thing, too. We had our first warm day in a long time, and the pump still has all Fast hardener in it. My UNI was setting up as I was installing the last few plies of it! I had to really hustle to get it all in there nicely, but I did and it worked out fine.
03/25/2009 (5 hours):
This is the step that never ends!
Today I didn't get MUCH done but it was important stuff. I got the tabs completely cut out and cleaned off, trimmed off the waste, and re-drilled the holes. I was able to install 1/4" drill bits with very minor tweaking, just a light tap with a file, so I'm pleased with that.
Word of advice: if you get to this step and you're very confident in your layup abilities, find some way to trim the excess tab width before it cures! At the very least, go for more like a 3.25" width rather than 3.8" as the plans call for. It would have been a lot less trimming, and less danger of damaging the leg underneath. Or maybe just leave the excess - it's several ounces of junk you don't need, but this isn't the worst spot to have a bit of excess.
One thing that did NOT go well is the holes are too low! In one photo you can see a spot where the hole is kissing the attach tab. The damage there is nothing - my tab goes farther onto the strut than it should, and this extra bump is what I gouged. But when I drill the holes out to their final size it will cause a problem. I looked through other builder logs and found that others have had this exact issue. I plan to do what they did - move the holes up slightly, then correct for it at the wheels later. No big deal. I don't even need to fill the current holes, because the new ones will be just a bit higher, and when drilled out to their final size, will overlap the current holes.
I took a moment and positioned the gear in the fuselage. It looked great! As the plans suggest, I'll have to do a bit of light tweaking with a file on my bulkhead holes, but I don't want to do that until I can get the bird upside down and position everything properly. Until then, I'm setting this piece aside and moving on to other items.
04-18-2009 (2 hours):
Today we flipped the plane over so I can install the mains. Flipping a Cozy is a big job best suited to 4-5 guys. I have round wooden supports to help with the job, but it's still very heavy and unwieldy (mine especially, because I have my strakes and turtleback on now!) To do the job with fewer people, we slung a rope and pulley up to the ceiling and tied it to the nose. I hauled on that while John lifted the actual Cozy and together we actually managed the job pretty easily - more easily than we had expected. Moving the sucker AROUND once we FLIPPED it was tricky, but we got the job done with a dolly under the nose and each us lifting one strake.
Installing the gear itself is a little tricky because I can't drop plumb lines to the floor the way the plans specify. I was pretty tired by this point, so I bagged on it for the day. Tomorrow I'll be back out, and the plan is to set up string lines and data points on the strake skin. That should give me what I need.
04-19-2009 (8 hours):
Today was a very frustrating day. I seemed to encounter setback after setback - drill bits breaking, my right angle DRILL breaking, my screws weren't long enough, etc. I felt like for every 10 minutes I actually spent working on the plane, I spent 30-40 trying to fix a tool or resolve an unproductive issue.
I did, however, more or less bludgeon my way through this step, and it's almost done. I started by redrilling the holes in the attach tabs, then installing the gear in the fuselage on 1/4" drill bit "studs". After a bit of finagling to get the holes perfect, I was very pleased with the results. My gear LE sits perfectly above FS 108.25. I'm at most 1/16" out without any adjustment required, and that was rewarding for a first attempt.
I took out the gear and installed the aluminum hardpoints. I hit a bit of trouble here. It's very difficult to work in my fuselage since it's mostly complete, and my Bondo didn't cure well so the attach tabs were floating all around. It took a lot of careful effort to chisel all the bad stuff back out of the hell hole, but I did it, slowly and carefully. Then I drilled the countersunk screw holes, only to find that my right-angle drill bit broke its weld! This product isn't exactly very high quality.
OK, off to the Borg. I got a new right-angle drill adapter, but this was much larger - 5" in overall depth. With a normal drill bit in it, it was too long to fit in the gear well! OK, be innovative - this is what Dremels are for, right? I cut off about an inch of the bit, and was off and running again. Unfortunately, about 5 holes away from being done, I broke my bit, and it was my only one of this size! Grrrrrrrrrrrrr! Well, I do only have five holes left to drill... And I do have this bench grinder... No problem, I ground a new end onto the bit. I'm not that good at this, and I sort of free-handed it by grinding a bit, comparing it to a "real" drill bit, and grinding a bit more. I'm no machinist, but it did cut the last five holes, so it worked OK.
I'm now more than a little frustrated, but not as much as I'm about to become! The next step is to flox the hardpoints onto the bulkheads. Fine, easy job. I'm even loaded with all Fast hardener, so maybe I can keep going later today. I sanded the bulkheads, mixed up some flox, buttered up my hardpoints, and put them in place, using the drill bits again for alignment. Now I ran into TWO more snags. First, my bulkheads (remember, these are built in Chapter 4, when you don't know what you're doing) weren't PERFECTLY flat. I mean, they were MOSTLY flat, but after all the layups/reinforcements they sat at a few thousandths of an angle. That's annoying because when you screw the hardpoints down it puts a LOT of tension on the drill bits used for alignment, and makes it very difficult to remove them! I got around that using pliers and hammers, but at the cost of getting my drill bits covered with flox, and setting up for a later frustration.
My second issue was my screws - the ones the plans call for weren't long enough! After all this time, I'm so used to working with AN bolts that I have a good supply of extras in a wide variety of lengths. It hadn't occurred to me to get that many countersunk screws - the plans really don't use them that much. So I had no way to finish this step! Well, sort of - for now, I just installed regular AN bolts so I could at least get the hardpoints in. I've ordered more screws, and hopefully the lengths I need will be here by Thursday, which is my next build day. (And hopefully I'll be able to get the AN bolts back out!)
Off to the next step. Drilling! I'd been sort of afraid of this particular step for a while, and that's why I had been holding off for so long. Well, it wasn't that bad. I had two each of Milwaukee bimetal hole saws in 0.75" and 0.625" sizes, with arbors designed to sit with a set screw on a 1/4" arbor. Perfect. I ran the long 12" bits through my landing gear, set up the hole saws, and went at it. I was careful to drill only most of the way through each section, to keep the holes aligned and supported, and moreover since I had two of each hole saw, I was able to adjust them as I went so each acted as a drilling bushing as its hole was made. I was pretty happy with the holes in my landing gear. A little light filing to clean up the holes, and my bushing/tubes went in with a few light taps from a hammer. Perfect.
Then the trouble started. I proceeded to set up for the fuselage drilling, and was pleased with my initial results - the bimetal hole saws made clean work of the aluminum hard points, which I had been nervous about. But it took a LONG time. Friction in the system was high, so I kept having to back out the whole assembly and clear chips and metal/fiberglass rings out of the hole saws. I did use some cutting lube while drilling the hardpoints - I don't know that it helped. It seemed to hold the chips in the drilling area, and that wasn't helpful at all. To make matters worse, I had a SLIGHT bit of flox on the drill bit, and the heat of drilling was curing it hyper-fast. At one point it took me nearly 45 minutes to get the whole assembly out, using pry bars, screwdrivers, and hammers, because the hole saw arbors had gotten floxed into place on the 1/4" drill bit, the hole saws had filled up with chips AND cured in there too, and the whole assembly was locked in place!
But I did get the job done. Finally, at the end of the day, I went to install the gear. My assembly is a VERY tight fit. I think it will go, but I didn't want to force it. I think I need to sand the faces of the steel bushings very slightly - I need a few more thousandths of clearance before the gear will pop in without flexing the bulkheads. And the AN bolt heads are in the way, so I need to install the countersunk screws. But despite all the issues, I'm relatively pleased - I think this whole mess turned out OK in the end!
04-22-2009 (3 hours):
Today my job was to get the bushings installed. My problem is that my bulkheads are either too close together, or my MKMGA spacers are too long. It's not a huge offset, but it's enough to make getting the gear to sit in the gear well almost impossible. So I started by milling the faces of the bushings - not a lot, just a few thousandths of an inch. But that's all I needed. Then I floxed the bushings in place and installed the studs to align them for cure. I aimed a hair dryer at each bushing, rotating it to another every 5 minutes, to accelerate the cure - this worked great.
Getting the studs back OUT proved to be a major difficulty. There's really no good way to do this, especially without damaging the studs. What I ended up doing was threading on a closed-end box wrench, then a washer (to protect the nut), then a nut. I then hammered at the box wrench as close to the stud as I could until it pulled out. Sort of a primitive slide hammer. It worked OK, I guess.
Next I installed the spacer assemblies in the gear legs, then installed the whole thing in the fuselage. It fit! What's more, it fits without ANY play, and the legs are still dead on where they should be. I did tweak the fore-aft offset of one side a bit with a screwdriver, then installed the studs again for alignment and made a flox bead around the bushings, leaving that to cure overnight.
Getting the studs back OUT to do the last steps - making the BID wraps over the spacers, and floxing/BIDing on the final washers, is going to be a BITCH. On one side I had to use a hammer to get the stud in, with pretty firm raps. I have no idea how to get it back out now or in the future without damaging the studs or bushings. The only two options I can think of are either to buy a REAL slide hammer and figure out some safe way to hook it up to the ends of the studs, or to drill a small hole in the firewall aimed directly at the studs, then use a long steel rod (like a drill bit with its head ground flat) to let me hammer at the back side of it. I'll have to do something tomorrow - that's when I do the last step!