Thu Jul 8 2010

Popup tipup modifications

OK, since I had one arm drilled, it was time to make the spacer block and the other arm. Here's the spacer block which goes just in front of the U bracket. It's 1/4 inch thick to allow the U bracket to fit between the two arms.

This rivet pattern will be opened up to #30 holes, but for now they're drilled #40.

After doing a double countersink, I squeezed two 3/32 rivets to temporarily hold this shebang together. Actually I didn't squeeze the rivets. See, the longest 3/32 rivets I had were AN426AD3-8, and that's the same as the thickness of the assembly. So I used a center punch to peen the shop head just enough to hold the assembly together. I'm going to have to get some longer rivets when it comes time to assemble this for real.

After a bunch of sanding, I had the UHMW blocks on either side reduced to the correct thickness. The outboard one was about 0.610 and the inboard one was about 0.660.