These helpful charts are so often used by machinists that one of our certified technicians put them together on one page for our customers. SEE BELOW PDF LINK or call us to get a card sent to you. Surface Feet Per Minute (SFPM) =RPM x.262 x Tool Diameter Revolutions per Minute =SFPM x 3.82 / Tool Diameter Feed Rate (Inches per minute) =RPM x Chip Load per Tooth x # of Flutes Chip Load per tooth =Inches per Minute / RPM / # of Flutes cnc machinists charts - CLICK HERE!!! fractional chart drill chart fractional drill chart drill sizes drill tap chart/sizes sfm for turning surface footage for lathe sfm calculator/formula chip load calculator chip per ...