Rudder final drilling

I rigged up a better solution for my air hoses today, then final drilled the few holes that need it in the rudder. Most of the rudder parts are pre-punched to final size, and just need a little deburring. Then I debuted the skins, getting ready for dimpling, then assembly.

Here is what I ended up with for air hoses:

It’s much better with the hose coming down from the ceiling than to be dragging it around on the floor. The coiled hoses are very light weight, and are only rated to 120 PSI, which is well above anything I’ll be using them for.

I made up a little template to assist with the trailing edge drilling. The holes need to be drilled perpendicular to the chord line of the trailing edge wedge, which turns out to be 6 degrees forward of square with the skin. I found that the drill naturally hits that angle because the trailing edge wedge is already drilled to that angle, and the skins are so thin, it’s easy to get it pretty close. On a couple of holes the drill caught the upper (left) skin, and ended up enlarging the hole slightly. Once dimpled, will see if I need to do anything about it.

I final drilled all the holes in the top ribs, and matched drilled one on the front, but didn’t get a picture.

Then it was onto deburring, which is very carefully done given how thin the skins are. I made up a practice piece to see how excessive debuting affects the hole, after dimpling. It’s amazing how a few spins with the deburring tool remove enough material to really expand the hole diameter once dimpled. I got all of the left skin done, and partly through the left one, but I’m so tired I need to go to bed now. Will tackle some more tomorrow.