Calculating Spindle Rpm - Shop fox M1111 Owner's Manual

Calculating Spindle
RPM
Closely follow the proper cutting speed and
proper feed to reduce undue strain on all mov-
ing parts and increase operator safety.
Prior to milling, determine the RPM needed to
cut your workpiece, then set the RPM on the
machine.
To determine the needed RPM, do these
steps:
1. Use the table in Figure 18 to determine
the cutting speed required for the material
of your workpiece.
2. Measure the diameter of your cutting tool
in inches.
3. Use the following formula to determine the
needed RPM for your operation:
(Cutting Speed x 4) /Tool Diameter = RPM
M1111 Mill with Dovetail Column
Cutting Speeds for High Speed Steel (HSS)
Cutting Tools
Workpiece Material
Aluminum & alloys
Brass & Bronze
Copper
Cast Iron, soft
Cast Iron, hard
Mild Steel
Cast Steel
Alloy Steel, hard
Tool Steel
Stainless Steel
Titanium
Plastics
Wood
Note: For carbide cutting tools, double the cutting
speed. These values are a guideline only. Refer
to the MACHINERY'S HANDBOOK for more detailed
information.
Figure 18. Cutting speed table for HSS cutting
-22-
Cutting Speed (sfm)
300
150
100
80
50
90
80
40
50
60
50
300-800
300-500
tools.