[Eric B]

About to start working on my -10 wings, and some of the first steps are to countersink a bunch of holes. (same for other models) When i built my HS, i got curleycues on the spar flanges as the material was removed from the holes, aorund the hole being worked on. To fix, i just buffed them smooth with a scotchbrite pad, but i don't wanna do that on the spar. Anybody got any suggestions on how to keep the curlycues at bay, so i won't feel like i need to trash my spars?

Thanks,
Eric

 

[PJSeipel]

I had that problem using the single hole countersink cutters. The ones with 3 flutes seem to not have that problem, although they are more prone to chatter if you don't have a good hole for the pilot to sit in.

PJ

 

[Jamie]

The anodized surface is brittle, but harder than bare aluminum, so you'll probably see that the countersink shavings will not scratch. It actually takes quite a bit of effort to scratch the anodized surface.

I've also noticed that countersinking with the hole oriented vertically allows the shavings to fall out of the spinning microstop...while countersinking a horizontal surface sort of causes the shavings to spin around with the countersink bit.

My real advice? Just build that thing! Don't sweat those sort of things...if you do scratch it...just buff it out and dab some primer on it and move on...otherwise you'll *never* finish.

- Jamie