March 23 & 24, 2020
Since the rear spar was completed yesterday, we finished the skeleton for the rest of the horizontal stab today and and then it was time to tackle the skin. The first rivets of the skin have to be bucked, which is the first time we’ll have to buck anything for real.
Before we were ready to rivet the skin we took an hour to practice our skills first. After about 100 practice rivets we felt reasonably settled into our roles. Paul would primarily command the bucking bar and I’d run the rivet gun.
Even after the practice it’s terrifying the first time you have to take a rivet gun to the skin for real. One slip and you’re out a week for shipping and quite a bit of cash for a new skin. Not to mention re-doing all the match drilling and priming. Luckily that didn’t happen.
We had a few rivets in the corners that just wouldn’t sit flush. After drilling them out once or twice, we ended up getting all but 2 to sit nicely. Those 2 had to be drilled up a size and replaced with the “Oops rivets” – rivets that are 1/8″ diameter but have the same size flush head as the 3/32″ rivets. I’m sure it won’t be the last time we use those. Overall though, I’m happy with the quality of the driven rivets. This certainly is a two person job to run the gun and hold the bucking bar, I’m really happy we’re building this together.
With the left side done, we continued on to the right side skin and progressed pretty smoothly. The pneumatic squeezer is still the best way to tackle any rivet that can be reached but we managed to get a rhythm with the rivet gun too.
Some of the pictures show primer that got scraped off from the bucking bar. In reality these areas still had plenty of protection, but the flash and angles make it look a lot worse than it is. Still, we biased towards hitting those areas with spot primer. We’ve learned to wrap the bucking bar in painter’s tape to prevent it from scraping so badly.
At the end of the day we had 8 holes along the rear spar that are never called out in the instructions. The drawing had the callouts for the rivets, but the instructions never had a step to install them. We went ahead and did it anyway, worst case we’ll have to drill them out if they’re not supposed to be there yet.
We’re saving all the fiber glass end cap work for a slightly later date. I’ve never done fiberglass work before, so I’m saving it all up so I can screw all the pieces up at the same time. But for now, it’s time to celebrate completing the horizontal stabilizer!!
Cheers,
-Kacy
(Total Build Hours: 65.5)