Hi, I’m trying to cut 3mm thick clear polycarbonate but having some difficulties with it sticking to the bit and ultimately ruining the surface. I’m using a 1/16 2 flute upcut and 635mm/min and 0.5 depth per pass. The cut always starts off well for the first 30 mins but then an accumulation of plastic occurs when the bit is doing a shallow pass. I’ve experimented with 15000-18000 rpm but all the same result. Any help is appreciated. Thanks.
Also, I see a lot of people using high speeds like 2000mm/min I’m kinda hesitant because I only have 1 of that bit size. 
Go faster. You’re more likely to break the bit by creating a melting situation. Decrease the depth of cut and take more passes.
Okay so for example would 0.3 and 1000 be a reasonable attempt?
I don’t know your machine.
I’d go faster.
If you’re unsure, cut shallower.
2000mm/min and 0.15
3000 @ 0.1
I’m using a workbee with grbl. I’m not sure if the sluggish default acceleration settings in grbl are making a difference to the speed that’s actually used.