Flaperon Counterweight Drilling Technique

[Marc Bourget]

The idea behind deburring is to remove stress risers in/on ? the lower exit of the hole drilled into the tube.

Once the material gets thin enough, the drill doesn't cut any more, it tears the metal. That creates stress risers. Knocking off these torn remnants is not the same as deburring the hole.

You're better off if you achieve a chamfer on the inside of the tube.

They make deburring tools for just this purpose.

FWIW

[thiggins]

Debur from the outside. This tool allows you to debur both sides of a hole from the outside, using the correct hooked blade.


https://www.cleavelandtool.com/produ...8b985755&_ss=r

[BobbyLucas]

Another tool made specifically for this task: Noga Reversible Deburring Tool (mini)

https://www.amazon.com/NOGA-Reversib...s%2C119&sr=8-2

[RFSchaller]

If you don’t have the fancy tool to keep the tube from rolling you can epoxy two parallel 1X2’s on a Piece of 2X4 with a1/2” gap in between and lay the tube in the gap to keep it from rolling while drilling.

[JMS1198]

I attempted to look up the tool number, without success…my friend gave it to me and he was a military sheet metal guy, 30 years ago…I did see other types of bushings though…sorry guys.

[thiggins]

Originally Posted by RFSchaller

If you don’t have the fancy tool to keep the tube from rolling you can epoxy two parallel 1X2’s on a Piece of 2X4 with a1/2” gap in between and lay the tube in the gap to keep it from rolling while drilling.

In the aviation aisle at HF…


Harbor Freight Tools Self-Centering Drill Press Jig - Item 92046 / 47993 https://hftools.com/app92046

[JMS1198]

I’m going to save some people a couple of hours of head scratching too…when building the right flaperon, the instructions say mirror the left, however this needs some interpretation. As confirmed by DOG Aviation, who called Vans, you have to switch the position of the left and right ribs (outer to inner and vice Versa, on the A1204 and the A1210) you will know that it’s correct because the A1207R will fit properly (I devoted two hours to this last night, running in place).