Short night tonight. We had a storm roll through and flood come streets while also disabling stoplights. As a result, my commute home was pretty ugly – instead of the normal ~20 minutes, it was over an hour. It honestly took so much out of me that I took a nap when I got home.

After that, though, I wanted to at least get the left wing on the stand. Josie helped me put it in place, and I set about getting it clamped in place. This ended up requiring me to modify the stands a bit – the pieces of angle to support the rear spar weren’t positioned quite right, so I had to do some customization. Nothing too serious though, and now the wing skeleton is securely in place. The only other thing I really need to do is get a couple of plumb bobs so I can ensure there’s no twist in the wing before I go to town match-drilling the skins and so forth.

Good news: Fixing that rib issue was pretty easy. I popped out to the garage after dinner and went to work. First order of business was to drill out the other two rivets holding the offending rib to the rear spar. That went fairly well, though it was a pain to drive the rivets out of their holes. I’m gradually learning that thicker materials = lots more grip strength for the rivet shaft = way more work to drive out. This is also another point in favor of putting the manufactured head on thinner material, because having to bang hard on a rivet to knock it out when it’s backed up by a thin rib is kind of scary. It’s really easy to bend the thin rib flange.

Anyway, with that rib freed, I unclecoed the other three wing walk ribs, and as I had hoped, I was able to pull the spar end out of the way enough for me to get in there and straighten the rib face. After that, it was straightforward to squeeze a new rivet; the hole seemed a touch oversize, but by pre squeezing the rivet a bit, I was able to get it set OK.

From there, I went to work on the rest of the wing walk ribs. These were straightforward too, until I got to the two inboard-most ribs. Here, there’s a lot of reinforcement material on the spar; there’s the long reinforcement fork that stretches outboard about 18”, plus another smaller reinforcement plate that only covers these two ribs. End result, there’s a lot of material thickness here. The plans call for -8 rivets here, but when I put one in and checked the length with my gauges, it seemed a little short. On the other hand, the -9 seemed a little long. I debated a bit and finally decided to just follow the plans.

Wrong choice. The shop head I made was way too thin. Time to drill out another one…I got the head off no problem, but tapping the rest out was a serious pain. Remember what I said about more material = more grip? This is where I really became convinced of that. I was really worried about bending the rib flange, so I ended up putting a couple of small C-clamps around the rivet to hold everything in place. It worked like a charm, but also scratched off some of my primer:

So I used the -9 rivets for those two inboard ribs, and that was the end of my rear spar riveting. Look Ma, no clecos!

FYI, the still-open holes in both of these pictures are for the flap brace and aileron gap seal, respectively. They get left open since those pieces won’t go on until much later.

I still had a bit of SEM primer left, so I went ahead and touched up the primer I’d messed up while taking care of that rivet:

And that settles the left skeleton! Tomorrow I’ll plan on moving this wing back to the stand and getting everything all straight and level for upcoming construction. Then I guess I’ll get to working on the right skeleton. I think things should end up being timed pretty well for me to clean and prime the right wing ribs this weekend, and maybe by next weekend I’ll have both skeletons on their stands. Then the real fun will start. (fuel tanks! Proseal! Oh my!)

Came home today to find a nice little present courtesy of Avery Tools. Longeron yoke, some long-reach 1/8” clecos, and a tube of Boelube for good measure. Finally, I can get back to this wing skeleton!

I got Josie to help me pull the skeleton off the stands and put it back on the workbench. Everything was still clecoed together, so it was just a matter of going to town on some rivets. Well, sort of…one consideration on this rear spar is that there are several different material thicknesses together, and thus several different rivet lengths to use. And there are also holes that need to be left open to accommodate the aileron gap seal and flap brace down the road.

I started on the outboard end; this is a particularly unusual spot in that it gets flush rivet instead of the typical universal head rivets. The reason for this is that the outboard aileron hinge bracket sits on top of this spot.

Outboard flush rivets:

The mocked-up aileron hinge bracket to illustrate why those flush heads are required:

From there I went on down the line and things progressed pretty quickly. The nice thing about squeezing rivets is that once you’ve got the squeezer adjusted for a particular rivet length and material thickness, you can breeze on down the line making nice consistent shop heads without the trial-and-error that comes with the rivet gun. Things went great until I got to the inboard end. It seems that I had a rib with a slightly bent flange, and I didn’t catch it before squeezing a rivet:

That’s a problem. I didn’t think much of it at first; after all, I’m to the point that drilling out rivets doesn’t stress me much. I drilled and popped the manufactured head off, then started tapping it with a punch, but it wasn’t moving. Then it occurred to me why: with that kind of a gap between the rib and spar, the rivet undoubtedly swelled up in the space between. I doubt it’d be possible to drive the rivet out without damaging the rib. So this is going to be a more involved repair than I originally thought.

The good news is that this is the fourth-most-inboard rib, and I haven’t squeezed any rivets in the other three ribs. My hope is that I can drill out the other two rivets in this bad rib and then be able to pull the rear spar out of the way enough to get this bad rivet out and straighten the rib flange. Worst case, I might have to drill out the five rivets in the main spar and remove the rib entirely. Hopefully I can avoid that, as the manufactured heads of those rivets are towards the inside of the skeleton, and drilling them out will be a chore…not to mention the concern of damaging the main spar in the process.

It was late by the time I realized the problem I had, so I decided this was a good time to call it a night. Much better to sleep on the problem instead of trying to attack it all willy-nilly. Tomorrow we’ll see if I can get this all fixed up.

Not much to report today. I recruited Josie to come out and help me rivet the ribs that I couldn’t do on my own. It was a bit odd at first (I may have some mild control-freak tendencies), but pretty soon we got into a good rhythm and before long everything was knocked out.

The dogs came out to hang with us as well; I figured it wouldn’t take much riveting to change their minds, but I was only half right. After about the second rivet, Mae retreated back into the kitchen, but Dood (yes, that’s his name) just kept lying on the floor without an apparent care in the world. So we decided to have mercy on his ears and put the Mutt Muffs we got for Mae on him.

I had originally planned to finish out the night by at least starting to squeeze the rear spar rivets, but after clecoing the spar in place, I discovered that I can’t squeeze them with the setup I have now. I have a long flush set for the squeezer that would allow me to get around the spar channel, but it’s too long to get it on the squeezer with the other set. I could shoot these as well, but access would be tougher than the main spar, and it’s a lot easier to get consistent results squeezing. So I’m going to order a longer on yoke this week and hold off on the rear spar rivets.

I figure tomorrow I’ll put the left wing on the stand and start match-drilling and generally prepping the right wing ribs. I might even be able to get all the way through cleaning and priming them tomorrow if I can actually get my butt in the garage early in the day. I need to get on building the other wing stand too…

Yes, that’s really all I did today. My work ethic hasn’t been so great, and a lot of the problem is me being a little insomniac. I stay up too late, then I’m tired the next day, I try to resist the afternoon nap urge, but inevitably I give in, and then at bedtime I’m not sleepy, and the cycle continues. We did get up at a decent hour today so we could take the dogs to the Houston Arboretum for a little walk through the woods. We wanted to go early in the morning before it got too hot, but seeing how this is Houston, it was still pretty hot for a 3/4 mile walk even at 10 AM. When we got home I was tired and sweaty, and then I realized that I needed to run to the grocery store. Long story short, I got that done along with some food prep and finally got out in the garage around 2.

Instead of jumping into riveting ribs today, I took a detour from the instructions. I’ve been reading over Jamie Painter’s build log from time to time, trying to get insight into upcoming tasks, and I ran across something useful while reading about building the tanks. It seems there are three nut plates on the inboard end of the spar, part of the tank attach system. This area of the spar is also where the wing walk will be; that is, the reinforced part of the wing that passengers will be stepping on. As such, the ribs are spaced much closer together. That means that if I wait until later to do these nutplates, I’ll have to work in a fairly confined space.

Here’s where the nutplates will live; each of those sets of one large and two small holes is a nutplate location.

There seems to be no reason why I can’t go ahead and install these nutplates now, while I can get the ribs out of the way and have good access back there. So I did it.

Actually, even with the ribs out of the way, it’s an interesting spot. The spar reinforcement plate doesn’t leave a lot of room to get a bucking bar in there. Squeezing is out of the question; the nutplates are too far away from an edge and the spar flange and forward reinforcement bars are too wide too. I ended up using my tungsten bucking bar here. Most everything went well, but on one rivet I let the bucking bar slip off, and the shop head ended up with a nice little step on it.

I considered leaving it in at first. Generally, a shop head like this is unacceptable, but for a nut plate, the rivet isn’t really taking any load; all it has to do is keep the nut plate from spinning. Once the bolt is installed, that will be the main load path. Still, I was bothered by the bad rivet, so I decided to drill it out. I got the head off OK, but realized I needed a second set of hands to back the nutplate while I punched out the rivet, lest I ruin the nutplate and then have to drill out the other rivet as well. And here Josie had just run out for a few errands. So I went back inside to take a break…which of course turned into the nap I’d sworn I wouldn’t take today.

Finally, I got back out later and had Josie help me punch out the rivet. It turned out it was a useless wait anyway; the nutplate was still bent and I still had to drill out the other rivet and replace it. Then it was back inside to call and talk to my parents before it got too late over in the Eastern time zone.

This is the nutplate I replaced. I still put an ugly shop head on the lower left rivet, smeared it a bit, but drilling it out will probably cause more damage than good, and as I mentioned before, it’s not as critical here to have perfect rivets. You can also get a better idea of how the spar reinforcement (the outer raised area) gets in the way.

And things are just as fun on the forward side. Notice the spar reinforcement bar below these rivets, covered in blue tape to prevent marring. I could barely get the rivet gun with the flush set into the outermost rivets.

While I’m still annoyed by these short weekend work days, it’s still better than not working at all, I suppose…

I started out my day by heading up to Weiser Air Park for the monthly lunch the local RV builders do. I hadn’t been to one in a few months due to other commitments, so it was nice to go hang out, talk about building, and most importantly drool other everyone else’s airplanes. One the guys who flew in today was in this sweet-looking RV-8. My practical side is a little unsure about painting an airplane in anything vaguely low-visibility, but I have to admit that this is a cool paint job.

After watching everyone depart – a process that culminated with a low high-speed pass from an RV-10 driver – I headed home, feeling motivated to get to work. That got a little sidetracked when I decided to lie down for a few minutes, whereupon staying up late Friday night caught up with me.

Finally, rejuvenated, I went out to the garage. Mindful of how long it’d been since I shot rivets, I did some practice runs with a few scrap pieces before going to work on the spar itself. I was still kind of nervous for the first few rivets, but before long I was getting into a good groove. And that, of course, is when things got interesting. I was on the inboard end of the wing, where the spar reinforcement bars make the top and bottom rivets slightly more difficult to see the shop head side. I had shot four of the five rivets on this rib just fine, and the last one was the topmost. I inserted the rivet, got the gun and bucking bar in place, squeezed the trigger for a bit, then bent down to check my progress.

I was shocked to see a tiny shop head. Wait, did I not get the rivet in all the way? I checked the other side – nope, the manufactured head is flush against the rib flange. What happened?

I was confused by this for longer than I’d like to admit, until the obvious occurred to me – somehow a shorter rivet must have gotten mixed in with the ones I was using. If I’d been in any other hole, I would have seen this before shooting, but it just so happened to be the hole where my vision was obstructed.

Well, time to get drilling. This turned out to be a pain; I got the manufactured head popped off pretty easily, and started trying to punch the rest of the rivet out, but that thing was in the hole quite securely. My level of violence wight he hammer continued to rise before I realized that this was exactly the mindset that caused things to get damaged. It was getting on towards dinner time anyway, so I left things alone, fired up the grill, and cooked off some brats. We ended up watching a movie with dinner, after which I went out and, with my mind calmed down some, got the rivet punched out (though not after drilling all the way through it and using pliers to help encourage it). The hole seemed good but maybe slightly oversized; not enough to need to drill out to the next larger size, but enough that I was worried about the shop head clinching (this tends to happen when there’s extra play in the hole).

Fortunately, there’s a well-known solution to this. I’d never tried it, but you can take a rivet squeezer and give the rivet a tiny bit of squeeze, just enough to swell the shaft and snug things up. It worked like a charm; I shot the rivet and then called it a night.

Tomorrow will be more fun. All the ribs I did today had their flanges facing left, which made it easy for me to shoot and buck. Some of the ribs, though, face the other direction. The only way I’d be able to shoot and buck those would be to switch hands and shoot left-handed. I’m not too confident with that ability, so I’ll probably get Josie tome come out and help.

Not much to see here. I got a somewhat earlier start today because I worked from home for the second half of the day. It sure helps to not have to sit in evening traffic to get home…

Anyway, straightforward stuff today. I started out by finding the outboard-most rib and bolting on the piece of angle that’s used to attach the skeleton to the stands, then I clecoed that rib in place before setting the spar onto the stand. From there, it was a fun game of putting each rib where it went. I guess my binary system worked OK, because I got everything right the first time, without any oddness. Then I took the whole assembly back off the stands and laid it on the workbench to cleco the rear spar on. This seemed preferable to sitting on the floor and trying to line things up and cleco at the same time.

Hey, that looks like part of an airplane:

From there, I grabbed a couple of wing skins and did another one of those “because I can” assemblies:

Then it was time for dinner and we decided to watch a movie afterwards. Maybe tomorrow I can bang some rivets? I’m a little skittish; it’s been over a year since I shot rivets with the gun, and that’s going to be a necessity here. Even better, I’ll almost surely have to use the offset set to get in some of these places. I guess I should probably get some practice in before I go to town on the wings…

Lesson of the day: it takes a lot longer to do, well, everything with the wings. There are more of everything and each piece is bigger…

First, I’ll rewind a bit. Saturday wasn’t entirely unproductive, but mostly so. We had some errands to run in the morning, and when we got home I felt bad enough that I went and laid in bed for several hours. My back has been bothering me off and on for a week or so, and it got pretty bad yesterday (this has been a sporadic occurrence ever since I messed it up slinging boxes for UPS when I was 18).

By the time I felt ok to get up and walk around some more, it had gotten late, which did have the positive effect of the temperature dropping. I decided that my goal for the night would be to cut the new pieces of wood I needed to extend the jack platforms on the wing stands. I had enough 2×6 left over that I ended up cutting four sections, which I’ll sandwich together and attach to the long support to give me an extra 3” of jack pad length. I also cut some of my leftover 3/4” MDF scraps into the new platforms. I did not, however, actually assemble anything.

Today’s goal was to get the wing ribs primed. I slept in again and got to work just before noon. The first order of business was to make a hole deburring pass on each rib. This included the holes I’d match-drilled to the spars previously, as well as the tooling holes in the rib face. I’d left those alone previously because I thought I’d be running conduit through them. Once that was done, I scraped the part ID sticker off each rib, then took them outside for a good cleaning. This was where I got to really enjoy the Texas heat for the first time. It probably took over an hour to scrub down all the ribs.

Prior to the cleaning, I’d set up a piece of rope across the backyard to hang the ribs from. I then found it necessary to anchor the bottoms of the ribs as well so they wouldn’t swing in the wind too much. Some small-gauge wire I had lying around worked well for this. Here are all the ribs hung up and ready to be sprayed:

Next I got a less in the scaling up that happens when moving to the wings from the empennage. I had two full cans of NAPA 7220 on hand, which I figured would be enough. WRONG. There were still some bare spots when I emptied the second can. Fortunately I still had some SEM leftover, so I used that to finish the job. Both primers are gray, but the SEM is slightly lighter, so my ribs have a sort of amusing mottled look to them.

Here are the finished ribs:

Tomorrow I’ll probably go ahead and fix the jack pad on the assembled wing stand, cleco the left skeleton together, and hang it on the stands for the time being. I probably won’t be able to get to riveting tomorrow. I had originally planned to assemble the other wing stand first, but now I’m thinking I’ll wait until I need it. That means I need to clean up a bunch of stuff I left lying around in anticipation of assembling that thing…so much stuff that I don’t even have workbench space available, which I’ll need to rivet the skeleton.

Hopefully I’ll feel OK after work tomorrow…