Carbide drill bits for carbon fiber?

[M&J]

Any of you using carbide bits for drilling carbon fiber? Thoughts-suggestions?

I have a variety of typical twist drills and they do work but dull quickly. A cobalt bit may get about 12 holes with the first 4-5 being good. Thereafter they get dull and chew the fibers leaving a not so clean hole. I'm using a wetting agent mixed with dish soap which I have been pleased with when drilling stone but those use diamond bits. Diamond bits are not available in the sizes I need for this and even some carbide may be overly $ to use.

When I drilled the scales for these, it was sad to have gone through 3 drill bits for the progression. Cost of making yet it still is sad.

[Ray Rogers]

I used cobalt bought in bulk from MSC . . .

[M&J]

Thanks Ray! Went hunting and found some MA Ford Hi Roc straight flute bits that averaged about $16/each. Not bad though I don't know how many good holes carbide is good for. Some of the articles list an acute cutting angle to shear the fibers and a straight flute isn't the recommended cutting profile. At 3-4X the cost from cobalt if it does 50 holes that's acceptable but that is a marginal improvement.

Drilled about 5 holes with the cobalt bit then used it on some titanium. That bit got stuck and broke off in the piece. The joys of dull bits. These are smaller bits at #55 and 1.5mm. Fortunate that these are not $.