V-stab rear spar done for real. Rest of the skeleton, not so much.

Short night in the garage today.  I decided to wait on attaching the skin and just finish up the skeleton tonight.  Finishing up the rear spar was a snap; all I had left to do was to rivet the VS-411 and VS-412 hinge brackets.  Those were a piece of cake, and went pretty quick.  Before proceeding, I went back over the plans and instructions and realized that completing the stab was going to be a little different than I thought.  I’d been expecting to rivet together the whole skeleton, both spars and all the ribs, and then attach the skin.  Turns out the actual procedure is to rivet the ribs to the front spar, then rivet the skin to that skeleton, and finally rivet the rear spar in place last to complete the assembly.  And that, my friends, is why we read and reread the instructions before doing anything.

Anyway, back to work…everything was going great.  Upper rib to front spar, piece of cake.  Middle rib to front spar, also piece of cake.  The bottom was a different story.  Here there are two ribs to attach to the spar, which really limits access on both sides of the rivets.  Plus there are three rivets; the outer two are easy to get to with the hand squeezer, but the center one is inaccessible.  To make things worse, the ribs meet that spar at a slight angle, so one side is really tight.  After staring and rubbing my chin for a while, I decided to give it a whirl with the offset set I have for the rivet gun and one of the more odd-shaped of my bucking bars.  Better yet, in order to get in a position to both rivet and hold the bucking bar, I had to switch hands, with the rivet gun in my left hand.  I practiced a few times just getting everything in position, until I was confident I could do this.  A few quick hits on the rivet gun, stop to recheck everything, double-check the bucking bar positioning, everything still looks OK.  So I gave a good blast with the rivet gun again, then stopped to check again…crap.  The shop head of the rivet isn’t square, it’s starting to drift a bit.  There won’t be any saving that, that’s for sure.

I elected to stop for the evening at that point.  I’m going to have to figure out a way to drill out that rivet without ruining anything, and it’s going to be fun considering the confined that contributed to it being a bad rivet in the first place.  In the meantime, it’s time for some research into how other builders have done this.  A better squeezer, one that uses swappable yokes, would be helpful here; my squeezer has a pretty shallow throat, which limits its usefulness.  A 3″ yoke would have made this a breeze, and the rivet gun never would have entered the picture.

Oh, and I forgot to order the replacement parts for the h-stab.

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