@Addicted It's funny you mentioned that, because I ended up buying the upcut version of the same bit.
My results with the upcut were slightly better than the ball nose downcut I was using before. Surprisingly this upcut has a cleaner cut and the paper on the top surface is less rough.I still have tearout of the paper on sharp corners though, which is the main issue I want to solve. I will have to try a flat downcut as you suggested though. If that doesn't work, the only other thing I can think of is slowing down the cuts. I am running 2200-2300 mmpm which does okay for the most part.
One concern I have with the upcut end mill is it seems to get paper buildup on the endmill while cutting, and I have already seen that cause a bunch of PCB burr bits to break. The PCB ones I recall had the cleanest cuts but broke too easily and I had to run at rates which made it take too long to cut a sheet out.
This is cut using the
Upcut 1/32 at 2250 mmpm. Those tail sections are the most common ones lift/tear the paper -- the cut paths try to start from the narrow end and cut inward when it happens. What I need it to do is cut the opposite direction on those cuts and I think it will fix the issue... I *could* manually hack the gcode... but I don't want to do that if I can avoid it.
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