Centroid Community CNC Support Forum

not really an acorn question, but I dont really have anyone to ask

I'm trying to machine some delrin and am struggling to get a nice surface finish. Side-milling works fine, but I cant figure out how to face it well.
It leaves little fuzzies and isnt nice and smooth like aluminum. It also seems like the chips dont really want to break.

Here is what Ive tried

1: Tormach Super fly - 3in fly cutter
9in/min, 10thou DOC, 3thou feed/tooth (ignore right side, didnt cut deep enough to get rid of saw marks) HSS 4flute 1/2in endmill
36in/min, 20thou DOC, 3thou feed/tooth
You can see the sides turned out fine with side-milling, just not the face Also I am not using any kind of coolant/ fluid, should I be? my thought was no since its plastic, but what do i know

Thoughts?

Figured it out from talking to a buddy

The key is you have to use brand new sharp cutters, I was just using the ones I used on aluminum since they were all set up in my tool library.
Re-decked it off with a new insert and only 3in/min
It feels like my surface plate now

Nice job, and thanks for telling the solution.

You'll also get better finishes with HSS since it can be sharpened finer than carbide.