User Guide

G0484 Gear Head Mill/Drill
-19-
To  determine  and  set  the  mill  to  the  needed 
cutting RPM
:
1.  Select  the  cutting  speed  required  for  the 
material of your workpiece using the table in 
Figure 15.
NOTICE
Failure  to  follow  RPM  and  Feed  Rate 
Guidelines  will  shorten  cutter  life  and  give 
poor workpiece results and may threaten 
operator safety from ejected parts or broken 
tools.
Choosing Spindle 
RPM
Never  shift gears  while mill/drill  or  mill is 
running; otherwise, the gear teeth will  be 
chipped or broken.
NOTICE
Cutting Speeds for High Speed Steel 
(HSS) cutting tools:
Workpiece Material Cutting Speed (sfm)
Aluminum & alloys 300
Brass & Bronze 150
Copper 100
Cast Iron, soft 80
Cast Iron, hard 50
Mild Steel 90
Cast Steel 80
Alloy Steel, hard 40
Tool Steel 50
Stainless Steel 60
Titanium 50
Plastics 300-800
Wood 300-500
2.  Measure the diameter of your  cutting  tool in 
inches.
3.  Use  the  following  formula  to  determine  the 
needed RPM for your operation:
  Note: You will only be able to get an approxi-
mate RPM value with the gearbox range and 
reduction levers.
4.  Move  the  mill  gearbox  levers  to  the  nearest 
milling speed RPM.
Figure 15. High speed steel cutting chart.
  Note:
  Double  the  cutting  speed  for  carbide 
cutting  tools.  These  values  are  a  guideline 
only. Refer to the MACHINERY'S HANDBOOK  
for more detailed information.










