I riveted the two inner-most in-spar ribs, stringers, and stringer-web together. No pictures, because I didn’t have a camera in the garage.
Berck: 2 hours
HS Ready to Rivet
Saturday was frustrating. We finished deburring all the holes in the horizontal stabilizer, and dimpled all the holes in the skins. Then I started counter-sinking the HS spars.
I started in the middle and worked my way out. The holes in the middle where the spar caps are were great. Unfortunately, I did a dozen or more holes further toward the outside that wound up elongated.
I’m still not sure what happened. I have lots of theories. I’m also apparently not the only one. The spar flange is angled outward slightly, which I didn’t realize and set it up in the drill press as though it were perpendicular. This can’t be the only problem, though, because this was also true for the ones with the spar cap. Something about the spar cap behind the rib helped keep it all lined during the countersinking. Additionally, the rip gets deformed temporarily when doing it on the drill press.
As soon as I realized what was going on (way too late), I tried switching to the air drill. That produced the same results. The internets suggested a slower drill, which didn’t help either. It also suggested that having something behind the spar while countersinking helped, too. So we clamped a block of wood to the spar, drilled it out, clecoed into the wood, and used the wood to align the bit while drilling.
This seems to have helped tremendously. I did this for the rest of the rear spar. The front spar went just fine without it. I’m really not sure what the problem is. I didn’t think countersinking was an entirely complicated process. I’m going to use “oops” rivets for the elongated holes. Van’s sells them, and I’ve placed an order.
Since I was frustrated, Randy suggested that we should take a break. So we took a rather lengthy break and went on a motorcycle ride down to Victor and back. That shortened our workday a bit.
I put in a few hours today, finished the countersinking, and dimpled all the ribs. Ready to start riveting, finally. I’m not sure we’re going to be ready for the wings in a month…
Berck: 9 hours, Randy: 6 hours, Jonah: 3/4 hour.