Choosing Spindle
RPM
NOTICE
Never shift gears while mill/drill or mill is running; otherwise, the gear teeth will be chipped or broken.
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.
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 | |
|
|
Wood |
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.
G0484 Gear Head Mill/Drill
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.
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.
