I make a lot of carbon kevlar panels and parts for rally car and always have the same problem 
when trimming & drilling parts.

When I cut the finished part to size I always get a fluffy dry cloth frayed edge not a sharp clean edge 
like when I make carbon parts. Why is this.
Even if I drill a hole right in the middle of a part it has a frayed edge.

My process is hand lay up 1x Carbon Kevlar, 2x Diolen, 1x carbon kevlar using epoxy resin and then vac bag.

Any help appreciated.

Add the picture please.

You're using a material that is renowned for its abrasion resistance, and then surprised when it doesn't abrade cleanly... 

Cut with angel grinder and then use finer grids (at least 400) to wet sand it.

Thank you for the reply. I am currently cutting with a 1mm cutting disc in a 4.5" grinder.

Do you start with a 400 grit or work your way up from 80/120 etc?

You can sand them off as above or if you've just got a few stragglers left, you can use a fresh scalpel blade to cut them off. Its an unfortunate side effect of the abrasion resistance and cut resistance of kevlar and diolen so it is quite normal to have these issues.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Many thanks for your help, Appreciate it.