Bit o priming

Well, bunch of stuff going on today and other things to work on, so I didn’t have a lot of time for the plane. I did manage to finish prepping the aileron gap fairings and get them cleaned and primed. Maybe tomorrow I can finish replacing the left outboard aileron hinge bracket and get the fairings in place. We shall see.

Posted in Wings | Hours Logged: 1.5

Aileron dimpling, brace countersink, and much more

I didn’t really get started in the garage until 1 or so, since I flew with Joy again this morning. (and beat the plane up a bit, but that’s another story…) I also had a prospective builder who wanted to stop by, see the project, and get his hands dirty a bit. I was getting started countersinking the flap braces when he showed up, so I went ahead and finished those in between talking about all sorts of build-related stuff.

Countersunk braces:

IMG 5396

From there, I got him to help me dimple the aileron skins, so they’re ready to have the stiffeners back riveted now, and then I can do the final bend of the trailing edge, assuming I ever get around to building a new bending brake:

IMG 5397

After that, knowing that for me riveting was the most mysterious skill to me before I started building, I took some time and drilled a couple of pieces of scrap for my friend to practice riveting on. He squeezed a few, both with my cheap squeezer and the totally-not-cheap Main Squeeze, then shot a few with the rivet gun. So now at least that mystery has been assuaged a bit for him. Not too long after that, he had to go, so it was back to work for me.

Next I cleaned, scuffed, and primed my replacement spar reinforcement and aileron bracket angle:

IMG 5393

Then I sat down and deburred all the rivet holes on the flap braces and aileron gap fairings. Yay, more deburring!

Unfortunately, it was while doing this that I cast a critical eye on the trims I made on the flap braces. When I made these cuts, I convinced myself that I was leaving sufficient edge distance between the cut line and the inboard most rivet hole, but upon looking at them again tonight, they just didn’t look right. So I looked up the real specs, measured, and…yep, I don’t have sufficient edge distance here. Time to put in an email to Van’s, I suppose. This might be an OK location to get away with this, but it’s not a call I feel like I should make. Worst case, replacements are $27 each, and maybe since my fuse kit is shipping this week they could just crate the replacement braces in with that. We shall see…

One of the edge distance offenders:

IMG 5403

Well, at least I can clean and prime the aileron gap fairings tomorrow. I’ll hold off on the flap braces for obvious reasons. I also have the new aileron hinge stuff to rivet, and all the aileron stiffeners.

Posted in Ailerons, Wings | Hours Logged: 4.5

Replacement parts

Got my little package from Van’s while I was at work today, so I figured I’d get those parts ready to prime tonight. It’s been almost two years(!) since I messed with the spar reinforcements for the first time, so I forgot that they don’t come predrilled at all:

IMG 5389

That’s slight annoying, since it means I have to use the spar as a drill guide, which means I have to drill upwards from inside the wing. I started by clamping the reinforcement in place and drilling the five holes through the spar flange and the top skin. Then I deburred and dimpled those holes, clecoed the reinforcement back in place, and drilled all the holes through the spar web. clecoing as I went. After deburring those holes, I countersunk the outboard holes for their flush rivets, since they’ll sit under the aileron hinge bracket.

Finished piece in place:

IMG 5392

I also reamed the holes in the bracket angle piece to full size and countersunk the one hole that gets a flush rivet. Finally, I removed the flap braces from the wing and peeled the vinyl off both the braces and the aileron gap fairings. Tomorrow I’ll try and get all those pieces deburred, dumped, and countersunk as required, then they’ll be ready to prime this weekend.

Posted in Wings | Hours Logged: 1.5

Aileron gap fairing, flap brace, misc

Started out with some miscellaneous small tasks tonight. First and foremost, I still needed to drill out the rivets holding my ruined angle piece to the aileron hinge bracket. If I was smart, I would have done this before ordering from Van’s, just in case I botched the removal and needed more parts. It wasn’t an issue though; I got the rivets drilled out with no problem.

Also, my shipmate form Avery came in, including a long universal head rivet set. This was just the thing I needed for the aileron bracket rivets; I set all the rivets on the inboard brackets in short order. I’m glad the new set works well, it makes me a lot more confident about riveting the repaired outboard bracket once I get my parts in.

Much better:

IMG 5382

Then I moved on to match drilling the aileron gap fairings. Pretty basic stuff here, but one thing I noticed was that even with every other hole between the fairing and the top skin clecoed, the skin still wanted to pillow away from the fairing as I was match drilling. So I also used cleco clamps by each hole to keep things nice and tight together:

IMG 5380

Next up were the flap braces. This is one of those weird spots where a provided part is 99% done, but requires some trivial work before it’ll fit. In this case, the inboard portion of the brace as provided interferes with the rear spar reinforcement fork, so a bit has to be trimmed off. It’s odd that this isn’t already done…I mean, they even provide little guide notches for laying out the cut line. Why not just provide the pieces like this? I dunno.

Cut line laid out:

IMG 5384

Trimmed brace clecoed to the spar, showing why the trim is required:

IMG 5386

And an overview of the brace in place:

IMG 5388

Once I got the flap braces match drilled, I called it a night. I want to get the fairings and braces fully prepped this week so I can shoot primer on them this weekend. The weather’s looking nice and I want to take advantage. Hopefully I’ll also get in my replacement parts before then, so I can get this prepped and ready for primer as well.

Posted in Wings | Hours Logged: 2.5

Final top skin riveting, pt II

Not a lot to report tonight, Josie was able to help me move the left wing to the bench so I could squeeze the top skin-rear spar rivets. That concludes riveting on the top skins, with the exception of a few rivets on the right spar reinforcement that I have to replace.

IMG 5375

With that done, I decided to cleco the left aileron gap fairing into place, mainly just to see it there. I’m going to wait before I match drill this, maybe tomorrow night; then I can do both flap braces at the same time. Those have to have a bit of trimming done before they can be clecoed and match drilled, though. More on that tomorrow (or whenever I do it)

IMG 5378

Posted in Wings | Hours Logged: 2

Misc wing stuff, ruined parts

I was originally going to work on the skin-spar rivets for the left wing today, but Josie pulled a muscle or something in her back yesterday, so I couldn’t really ask her to help move that wing to the workbench. Instead I decided to finish the right wing riveting and then work on the aileron brackets and maybe the flap brace and aileron gap seal.

The leftover rivets on the right skin were all in the vicinity of the inboard reinforcement forks. The outboard group of these were pretty easy to do with the squeezer, but further inboard, where there’s a second small reinforcement plate, things got tougher. Even the thin-nose yoke wouldn’t fit between the unsqueezed rivet tail and the shop heads on the reinforcement. I tried using the rivet gun and a thin bucking bar on those, but the results were rather unpleasant:

IMG 5348

After drilling out that rivet, I decided to change my approach. The plans call for -4 length rivets here, but they’re a little on the short side, so I was using -4.5s instead. A quick test showed that a -4 rivet was enough shorter that I *could* squeeze with the thin-nose yoke in that case. So I decided that in this case, having slightly undersize heads was a better choice than the damage that might result from continuing to try and shoot the longer rivets.

With those rivets done, it was on to the aileron brackets. An immediate problem presented itself here: The bottommost rivets between the brackets and the spar are supposed to be flush rivets, so those holes need to be countersunk. This would have been better done before the entire bracket was assembled, but that ship has definitely sailed. I spent quite a bit of time trying to figure out a way to countersink here. My “trimmed” cage fit in place OK, but the drill chuck conflicted with the bracket body, so it was no use. So I decided to try and work something out using the drill press. First I tried chucking the extension for my deburring tool in the drill press (so I could then screw the countersink bit into it), but that did not go well. When I turned on the drill press, that extension wobbled briefly before ejecting itself at high speed and bouncing off my forearm. This left a nice bruise on my arm and also bent that extension, thereby ruining it.

But hey, since it was ruined, I might as well modify it for my current task. So I cut off the bent portion and now I was able to securely chuck it in the drill press:

IMG 5349

My strategy here was to use the drill press table height as a way to set countersink depth. I’d put it at a height where full extension of the press gave me a proper countersink. I was skeptical of whether I could be very accurate this way, but a couple of test runs on scrap showed that it worked surprisingly well. In no time I had the brackets countersunk. Problem solved!

Of course there was another problem. Each inboard brackets interfered with the shop head of the skin rivet above it. My first tactic to remedy this was to squeeze the skin rivets a bit more; I got them down to minimum acceptable height but there was still interference, so I resorted to filing the tops of the brackets to provide clearance:

IMG 5351

I shot a bit of touch-up primer on the brackets and let them dry a bit outside while I turned my attention to the outboard brackets. Riveting these was fun; there wasn’t good access for the squeezer, so I had to use the gun. Even better, there wasn’t good access to use my normal straight set, so I resorted to a double offset set. I really don’t like using that thing, though I made use of a VAF tip to prevent the set from rotating while I was shooting (and proving the duct tape is indispensable):

IMG 5353

The reason I don’t like the double offset set is that it’s tough to keep the set hitting straight down. This was how I ruined a wing rib back when I was riveting it to the main spar, and it bit me again here. I had one bracket rivet that I couldn’t seem to get fully set. After a couple of hits, I went at it again and the manufactured head actually popped right off. I’d been inadvertently applying a side load to it, enough to shear the head right off:

IMG 5355

Well, at least it was easy to drill out. But that got me looking at that rivet right under it, which I was pretty sure I’d smeared the head on as well. I decided to drill it out and replace it. Well, turns out I was right about the head being smeared; I carefully drilled in the center of the head, and what I saw after popping the head off was that I’d made a second hole in the bracket about 1/16 off-center from the original:

IMG 5357

Well, the bracket was clearly toast at this point. The good news was that I’d only need to replace this angle piece, and not the whole assembly, assuming I didn’t foul anything else up while removing it. So it was time to go to town drilling out the rest of the rivets. I managed to do it without further damaging the bracket, but when I pulled the bracket off, I discovered that I’d drilled through the bracket on that original hole and into the spar reinforcement:

IMG 5362

Well, at least it’s not all the way through into the spar. But now I get to drill out even more rivets, and the reinforcement has to be replaced as well. (grumble) Some of the rivets holding that reinforcement in place were surprisingly stubborn. It took a while to get them all out, but finally the reinforcement was removed without any further damage:

IMG 5363

The good news is the the outboard bracket on the left wing went on OK, probably because the riveting position was less awkward:

IMG 5366

So now I’ve got some parts to order. I’m also going to order some stuff from Avery, specifically a long straight rivet set for situations like this. The straight set should allow me to set these rivets without the nasty side load tendency of the offset. I won’t be trying to rivet the inboard brackets until I get that in.

I’m not sure what I’ll work on this week – maybe the skin rivets on the left wing if Josie can help me move it, otherwise I guess I’ll go back to working on the ailerons. I can get the skins dimpled and then rivet the stiffeners in place, maybe finish the trailing edge bends once I build another bending brake.

Posted in Wings | Hours Logged: 6

Final top skin riveting, pt I

Kind of a token night of work this time. I considered taking the night off, but I like the feeling of momentum I have on the project right now, so I figured I’d at least do a little bit.

What I wanted to work on was squeezing the rivets between the trailing edge of the top skins and the rear spar. Initially I tried squeezing those with the wings in the cradle, but that was rather challenging. So I got Josie to come out and help me move the right wing to the workbench:

IMG 5346

After a fair amount of squeezing, I had almost all the trailing edge rivets done:

IMG 5339

IMG 5340

The remaining rivets are on the inboard end, where the spar channel is reinforced by a doubler. Access there is going to be tight, so I’m going to do those another night. I might actually have to shoots those, especially the lat few inboard ones, where there are two doublers. There’s just precious little space to work here, and I don’t think even the thin-nose squeezer yoke will work here: (also, I need to clean my camera lens)

IMG 5344

Posted in Wings | Hours Logged: 1

Wing storage cart

As planned, I went in and left work early today. Got home not too long after 5, changed, and went right to work on the wing cart. The tough part of this is that, since I was recycling the bases for the wing stands into the cart, once I started, I was committed to finishing this thing, unless I could find somewhere to lay the wings overnight.

First I unbolted/unclamped the wings from the stands, then got Josie to come out and help me carry them out of the garage. We just set them out in the grass while I worked:

IMG 5330

Then there was a lot of unscrewing and unbolting to take the stands off the bases and get the bases apart. I managed to get it done before it got dark, and so I was able to cut the long 2x6s to final length in daylight instead of having to set up a work light or something. Then I assembled the lower channel of the cart; this was a modification of the “normal” cart design I made. Instead of having a single plank serve as the cart’s “backbone,” I used two 2x6s, with a 2×4 in between. The result was a U-shaped channel at the bottom of the cart. I also added two more 2x6s at the top running lengthwise. This creates a nice little pocket between the wings where I can store the bottom wing skins, and thusly solves a logistical and organizational problem.

I was going to add some diagonal braces for stability, but with just the channel and two more 2x6s, this thing is pretty much rock-solid:

IMG 5332

With the bottom wing skins stored in the middle:

IMG 5334

Then I rolled the beast out into the driveway and we loaded the wings into it. Perfect fit!

IMG 5335

IMG 5338

I quit at this point; it was almost 9 and I hadn’t even had dinner. I still need to clean up the garage from all this work and get things rearranged at some point. My next task on the wings will be squeezing all those remaining skin rivets, and then I can fit the flap brace and aileron gap fairing to each wing. I might be able to get the control surfaces done before the fuse kit arrives in a couple weeks; if not, it won’t be a huge deal.

Posted in Wings | Hours Logged: 3.5

Rivet QA, wing cart work

Tonight I just went out, inspected the rivets we shot last night, and marked the few that needed to be shot a little more. All told it was maybe 20 or so, not bad at all. It would have been a short work session, except that last night Josie also pointed out that the rivets through the leading edge skin and into the spar looked like their shop heads were undersize. Sure enough, I checked and they were. Guess I was a little overeager that night. I got out the squeezer and easily fixed all of the rivets on the bottom, but the tops ones were now inaccessible since the top skins were on. So after fixing the few bad rivets from last night, we went down the line on both wings and hit up all those LE rivets again.

So tomorrow I’m going to go in to work early so I can head out early and shoot for getting the wings off the stands and the storage cart built. I did run into a slight hiccup tonight – I bought some adhesive foam weatherstripping to pad the end of the cart where the leading edge will sit in it, but when I tried a test-fit with the wings, the weatherstripping gripped the LE skin and pulled right off the wood face. So that’s not going to work like I’d hoped. I may need to get a different material or something, I dunno. Or I could cut narrow strips of the carpet I have lying around and attach it with carpet tape, but that’ll be tedious.

Update: I went out and played with the cart stuff again. This time I stuck the weatherstripping in place with carpet tape instead of relying on the rather weal weatherstripping adhesive. I also left the paper backing on the non-adhesive side of the weatherstripping to promote it not sticking to the aluminum skin. End result: it goes onto the leading edge nicely.

Posted in Wings | Hours Logged: 2

Wing skin riveting done*

We jumped right into skin riveting after dinner tonight. Not really a lot to comment on, just more of the same stuff from the last couple of times. Only difference is that we got through the rest of the right skin tonight. I won’t quite say we’re “done” done, since I still want to go and check the shop heads. If the left skin is any indication, there will be a handful we’ll need to go back and hit up a touch more. But enough is enough for tonight.

Finished* right wing top skin:

IMG 5326

I did make a slight boo-boo on one rivet. Guess I held the gun at a bit of an angle and put a little smiley face dent under the rivet. No worries though, it’ll disappear under the paint:

IMG 5328

Posted in Wings | Hours Logged: 2