мельница смм 97 selsus. Feed and Speed Calculator for CNC Machinist''s CNCCookbook. Surface Speed (SFM or SMM in Metric): This is a measure of how fast the tool and AFPT: That business of "Chip Thinning" and "AFPT" on the mill cutter screens.. earlier, so we have to cut our feedrate from 108.6 IPM down to about 97