Forward tunnel cover problem

[jlfernan]

This was a bad day. Why do things that seem simple, kick my a..! Doing the tunnel cover everything was going fine till I dimpled the holes for the cover itself. The skin warped slightly but I was able to straighten it pretty well. I still had a bit of an alignment problem when I went to assemble it. My question is, I know the standard is for material .040 or less you dimple. But how do I keep the skin from warping? The misalignment put side pressure on the rivets and several bent over. Now i'm sure this part is not structural, but it still bugs me. Also, even using a drill press, some of the 5/32 holes don't come out round, they seem triangular. Any suggestions on how to assemble this thing without pulling out what little hair I have left?

 

[Davepar]

Light pressure and high speed help to prevent triangular holes. Once you have a triangle hole, it's hard to fix without a reamer.

Not sure about your cover problem. Do you have a picture? Also, .040 can be countersunk for an AD3 rivet if that's easier.

 

[dan]

If things are deforming when you're dimpling, you're either not dimpling enough (likely) or you're just stretching the heck out of it (unlikely).