Yet another Spar Flange countersink Question

[Surfdoc]

In reference to Section 7 copied from the manual below:

Machine countersink (trying to dimple the 0.063 thick spar flange will result in severe distortion!) the platenut attach holes in the W-906A spar flange. See Section 5E. Use A Microstop Countersink With A #30 Pilot To Countersink The Screw Holes In The Spar To The Proper Depth For The #8 Screw. The pilot will center in the countersunk platenut well enough to keep the hole round and concentric. (Tip: cut a #8 screw short so that it enters the K1100 nutplate easily and use it to gage the depth.)

My countersink is not fitting in the nutplate as instructed (it seems a bit loose). Worked fine on the top flange and now moved on the bottom flange and I am not getting concentric nice countersinks with the #30 bit. Yes, the platenuts have been riveted on prior to countersinking per the instructions. I tried multiple drills just to be sure it wasn't the chuck. And of course I set the depth on a piece of stock before touching the spar and all was fine. I stopped at the third whole wondering if any one had suggestions...

Thanks as usual!

 

[PilotjohnS]

My take

I did not have trouble with this. If I recall, I used a countersink with a #30 pilot. It might have been a little loose, but came out fine for me. Good luck.

Maybe try and put a screw in to make sure platenut is centered?