Calculating Spindle

Speed

Closely follow the proper spindle speed and proper feed rate to produce good results, reduce undue strain on all moving parts and increase operator safety.

Prior to milling, determine the spindle speed needed to cut your workpiece, then set the speed on the machine.

To determine the needed spindle speed:

1.Use the table in Figure 23 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 spindle RPM for your operation:

(Cutting Speed x 4) /Tool Diameter = RPM

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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

Note: For carbide cutting tools, double the cut- ting speed. These values are a guideline only. Refer to the MACHINERY'S HANDBOOK for more detailed information.

Figure 23. Cutting speed table for HSS cutting

tools.

Model G0704 (Mfg. since 09/09)

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Image 28
Grizzly G0704 owner manual Calculating Spindle Speed, To determine the needed spindle speed