Hello Fellas machinists.

As the title states, I need some guidance about cutting Carbon fiber sheets. I will explain my problems as much as I can, and if I have forgotten something, please point it out.


I have been cutting CFRP materials for some time, and there are differences in results between each job.

For example, when I was cutting without any coolant, I have had best results so far. Holes are on spot, round and there were no quick tool wear.

As I wanted to remove the dust from my workshop, I have started using water as coolant. Well, not coolant as more of a dust blocker. And not, After a single plate, tool wears out pretty quickly.

Tools in question are not cheap ones: Carbide Diamond pattern Router bits, Diamond pattern and Diamond Coated. with 3.175 mm of diameter.

Machine setup:

Fully rigid machine which is designed for machining aluminium and steel. Problem is not in rigidity.

Spindle speed is on 5500 RPM and feed speed is on 650 mm/min.

DoC: 0.75mm

Problem: Tools wear out very quick, and therefor tolerances become a problem very quickly. Required holes are also not circular as more of a ellipse. Small but noticeable ellipse.

When using no dust blocker (Water), end bits last much longer, which is so strange to me, and the tolerances are much much better using just a vacuum cleaner as a dust removal.

As I cant afford to have my workshop be full of dust, can anyone give me an advice on how to optimize milling, to prolong the end bit life, while keeping the dust at water control.

Thank you