Hey guys I want to countersink some graphite parts for 4-40 button head screws but can't find anything in that size. What is evrybody using and where can I buy one.

I use my Dremel with a blunt grinding stone, works great.

Good idea Trerc never occured to me. I'll give it a try. Thanks!

That will work once you find the right angle. It takes a 100 degree countersink.

The correct countersink for 4-40 flat head screws is 82 degrees. Button head screws do not need countersinks. These can be purchased at either MSC or McMaster Carr.

Dave Irrgang

I got the countersink I use for carbon fiber from McMaster (www.mcmaster.com), part number 2944A13, described as: "Solid-Carbide Single-Flute Countersink 1/4" Body Dia, 1/4" Shank Dia, 2" O'all Length".

The description at McMaster says a single flute countersink is recommended for plastics. This has worked very well for me.

Thanks much guys I'm off to Mcmaster.com!