Originally Posted by Jack000  flute count is important too. Especially for plastics a 2 flute is better since it gives more room for the material to escape. (correct me if I'm wrong, I'm not an expert!)
Also, make sure the cutting length of the bit is long enough to fit all the way through the material you're cutting. I bought a 1/8 bit with 1/4 shank only to find that it can't 'poke' through the wood before the 'neck' of the bit hits the surface. I now use a 1/8 bit and 1/4 adapter bushing. |
Sorry Jack,
I disagree on the plastic. You want an O-flute which is a single flute for plastic. This increases chip load which helps with cooling and reduces the chance of melting all the swarf back into clumps and clogging everything up. Look at the feeds and speeds stuff on onsrudcutter.com. Lots of good info there. Run the router slow if you have variable speed and run the ipm of your cnc as high as you are comfortable with depending on part size and geometry.
A 2 flute spiral will also work, but if you buy a bit just for plastic, get the O-flute.