I tried every Onsrud cutter they recommended and they worked like *crap*.
I followed their recommendations to a T, tried changing my cutting conditions and never got them to work worth a damn.
I do not cut very thin stuff, nor do I do routing (although I cut parts out of acrylic on my VMC).
In my experience, HSS seems to give a better finish than carbide. I was told HSS cutters hold a sharper edge. I have a piece of 1/2" acrylic block on my desk right now, I cut it out with a 1/2" eight flute finishing cutter (this one is carbide). The finish is not crystal clear, but it's damn close. It's a 1/2" thick block, 2" x 2" square. If I hold it up against my computer screen edge on (I cut out 4 sides), I can read text through it no problem - so it's pretty damn clear.
That was around 30ipm, full depth, 1/4" on the width, shoulder cut, 6000rpm with coolant. Coolant makes ALL the difference. I 3D profile acrylic all day long - without coolant it's hazy with coolant I get a very clear (almost crystalline) finish.  |