Grizzly G0619 owner manual Calculating Spindle, To determine the needed RPM

Calculating Spindle

RPM

Closely follow the proper cutting speed and prop- er feed to reduce undue strain on all moving 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:

1.Use the table in Figure 19 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

G0619 DELUXE SMALL MILL/DRILL

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 19. Cutting speed table for HSS cutting

tools.

-21-