Mistake Proofing.

[bryjarmoc]

I work in aerospace industry. Obviously we do A LOT of drilling and riveting. My question is that we have a high reject rate for Counter sinks being the incorrect size. Are there any tools/devisces that would mistake proof the drill bit(s) to where it would virtually impossible to drill a bad "countersink"?

 

[mcgyvr]

Proper fixturing/support.
Are these holes being done with a hand drill or a drill press type setup?

A drill press can easily be setup to only drill to a certain depth. Set that and your Csinks will all be the same.

A hand drill/movable unit you can maybe setup a collar that would only allow the bit to go so deep.

 

[tomwalz]

Bad how - wrong size drill bit?

Maybe something like the Jack Rabbit.

http://www.carbideprocessors.com/level2store/jackrabbit/jackrabbit.htm

Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

 

[mfgenggear]

There is a drill & c'sk attachment with a miro stop that controls the depth of the and diameter of the c'sk.
in other words it's adjustable.

I have been out of thr loop in aircraft assy , so i do not remember who mfgs it.

but it should give you a lead.

I will google it if I find it i will post it.

 

[bryjarmoc]

they are actual hand drilled. I got more information and part of the issue is that because it is sheet metal, depending on where the counter sink needs to be done the "drill setup" will drill different depths. The "where" meaning that if there is a stiffener/stringer on the opposite of the sheet metal will cause a variation of depth with the same hand drill setup.

Let me know if this makes sense.

 

[hydtools]

Use a drill stop similar to this:

http://www.tooled-up.com/Product.asp?PID=32639

Ted

 

[mfgenggear]

This is what I had in mind

http://www.murphyair.com/SUPPORT/Techtips/techtip3.htm

 

[mfgenggear]

Bingo hit the target

http://www.yardstore.com/browse.cfm/2,333.html