Help on Machining Polyethylene

[pressurerelief]

I have a sheet of polyethylene I need to mill some parts from. Basically just some tool mounts for Storz couplings at the local firehouse. Think slotting, straight and arcs. Can anyone give me an idea on tools, geometry, feeds and speeds for this as opposed to machining 12L14 versus wood, etc. Can I use HSS or Carbide end mills or would a router bit be more effective?

P/R

[lwalker]

I picked up some sheets of HIgh Density polyethylene last year and found it really easy to work with. I use HSS endmills at aluminum speeds and simply feed as fast as I can (don't have power feed). The only problem I've found is that if speeds are too high, it can start to melt, but I've really only encountered that when drilling deep holes.

The stuff cuts like butter and I really like working with it.

[b2u44]

I fully agree with lwalker. Additionally, I usually use an air-gun to blow chips away from the cutting zone for any type of plastic. Otherwise, the chips can stick to the cutting tool and increase your chance of melting the workpiece.