Drilling the counterbalance pipes^3h

A short drilling session to prepare the counterbalance.

The counterbalance is just a galvanized water pipe that sits in front of the aileron.

Today, I drilled them to the leading skin. Later I've realized that my mistake was to drill them without any other supporting structure (the nose ribs, the spar) -- once pipe is drilled, it cannot be adjusted! However (and this is a message from the future), it worked out okay for the left aileron.

First, I clamped the pipe to the nose skin. I pushed the pipe as forward as possible.

Then I drilled the holes, first using the #40 drill bit, followed by a #30 reamer. It's absolutely not the way to use reamers (they are only to remove a small amount of material, say, up to 0.015" inches), but I am not very successful upsizing holes in steel and I didn't want to drill #30 holes. It worked well (but my reamer is probably completely trashed now).

Then I used a 120° countersink cutter to make countersinks for the CS4-4 rivets (120° because CS4-4 uses that instead of 100° of AN426).

To make the dimples, I used a holder for the dimpling bits and smashed it with a hammer against the skin and the pipe. In that process, countersinks in the pipe work as female dies.

And that was it!