Routing Teflon on the CNC

Dealing with hold-down and clean cutting issues when routing small parts from an extremely slippery material. August 3, 2009

Has anybody had any experience routing 1/8" teflon on a CNC router? I need to route 4.5 inch diameter circles.

Forum Responses
(CNC Forum)
From contributor T:
Onsrud Cutters Technical department recommends using a single flute straight edge O-flute solid carbide router bit if you wish to cut all the way through. They said that you could use an up-cut version of the same tool if you were willing to leave just a skin of material on the bottom to prevent the cut parts from moving. The up-cut bit will give you the best edge quality, but the straight flute tool will allow you to cut out your parts completely without dislodging the cut parts from the hold down. You should use feeds and speeds recommended for soft plastics.

From the original questioner:
What about using a down-shear and cutting all the way through?

From contributor T:
They don't recommend it in this material. They feel it may melt the product due to lack of chip flow. Unless your part is mounted on a pod above the bed, then you should be able to make that work.

From contributor J:
There are a number of sheet materials that have a tendency to "slide". Materials such as Delrin, UHMW, and HDPE can be similar to teflon in this regard. If you are still having issues look into GRABber for vacuum hold-down assistance.

From contributor C:
We have had good luck using a 3 flute slow spiral. You still get the chip extraction but without as much pulling the pc up. But, with any up-cut and cutting small parts itís always a concern.

From contributor G:
Use a straight 1/4" "O" flute. You will not have any problems with melting this material, it's teflon. Dedicate a spoilboard with vacuum grooves, holes drilled to the platten and gasket around each piece. Cut all the way through 100-400 ipm at 18,000 rpmís. It cuts like butter. We do this type of stuff day in and day out. Don't try to get cute thinking you might get by with a less spoilboard. This material is way too expensive to make bad parts. Not including material, your price should be around $0.30 - $0.40 each plus a $60.00 set up.