Cutting plastic with 3×3 cnc router machine. VELOX CNC model VR3636. Feed rate of the roughing was set to 45 IPM at .250″ depth of cut, 20K RPM, .500″ diameter cutter, 2 flute end mill. The finish pass was at 20IPM. We used VisualMill as the CAM. Mach 3 control software was connected to the cnc machine. Mach 3 worked great with the helical ramping in of the rough pass. Rough and finish passes were made in the program. We used 4 tabs to hold the piece in place but would have preferred a vacuum table.
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