What is best way to do it? I mean final product
I want just a clean cut and holes. Do i need some special drill bit? 20-25mm hole needed

You need to have some very good carbide drills at a minimum, especially with kevlar as it furs up even in a cured state. Trouble is a 25mm carbide drill will be very expensive so you have a few choices, get a smaller drill and chain drill the hole then finish with a sanding bobbin or find a hole saw with a smaller diameter then clean up.

I have found that just about the only thing that reliably cuts the kevlar "fuzz" are Diamond tools..

The specialized diamond coated drills used for cutting large holes in glass can sometimes be used running them at high speeds, and cooling them with water, which incidentally also removes the dust.




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Do these get rid of the fuzz or do they just reduce it. I am getting back into composites after 10 years of manufacturing years ago and I remember that fuzz was a big issue and ended up using toenail clippers to get rid of most of it. These were pretty close to the blades we were using to cut our parts. Worked AMAZING for carbon stuff.