Hey all,
I'm working on cutting some mold surfaces and the way I'm doing it currently is I rough it out leaving 0.03" on all surfaces with a square end mill. My depth of cut is also 0.03" so it creates a stepped surface. Then I come back with a ball end mill and run it with whatever stepover creates 0.0001" scallop height as calculated by mastercam. In short this is an extremely small stepover, but it produces the surface roughness that is required. However, visually there are little marred spots on the surface from what looks to be chip rubbing. I'm concerned with chip thinning at such a small radial engagement. Is there any good way to overcome this? Could it be a feeds/speeds problem?
I have a 4 flute 1/4" ball carbide running at 80 ipm and 6100 RPM
I also have a 2 flue 1/2" ball carbide running at 60 ipm and 3000 RPM
Thanks!