Centre Section Bulkhead #10 Countersink

[Richard Connell]

I think I'm going mad.
Ive drilled all the WD-1021-PC Landing gear mounts to the bulkhead with a #12 drill as instructed.
I need to machine countersink the 2 holes shown for a #10 screw.
My #10 countersink pilot clearly won't go in a #12 hole.
What am I missing?
How do I countersink these holes. Is such thing as a #12 pilot countersink?

[berck]

Confusingly, you need a #12 countersink cutter, because the cutters are hole sizes not screw sizes.

A #10 countersink cutter is worthless to us, but I suspect that you, like me, got the Cleaveland RV kit which comes with one. It should have come with a #12 countersink cutter for #10 screws, but instead came with a countersink cutter that not only will we not use, but which will confuse us at every opportunity.

I had the same problem at the same time, ordered a #12 cutter.

[Richard Connell]

Thanks Berck
That makes perfect sense. Thanks for clarifying.
The #10 cutter has been sitting in the tool cabinet unused since about 2003.
Never used it on the -7.
#12 ordered!

[Tassie]

Hopefully you have a large hammer in that toolkit, to beat the landing gear mounts into submission.

[Richard Connell]

Originally Posted by Tassie

Hopefully you have a large hammer in that toolkit, to beat the landing gear mounts into submission.

Ha. Not too bad thankfully Adrian.
No issues getting them aligned and drilled on the center section.
But It's early days!

[rvanstory]

Originally Posted by Richard Connell

I need to machine countersink the 2 holes shown for a #10 screw.
My #10 countersink pilot clearly won't go in a #12 hole.

FWIW, my tool kit (from Isham) had a 3/16" countersink in the kit. I used that and it worked just fine for #12 holes.