Spindle Speed - Grizzly G0808 Owner's Manual

Spindle Speed

Using the correct spindle speed is important for
safe and satisfactory results, as well as maximiz-
ing tool life.
To set the spindle speed for your operation, you
will need to: 1) Determine the best spindle speed
for the cutting task, and 2) configure the spindle
speed range lever and spindle speed dial to pro-
duce the required spindle speed.
Determining Spindle Speed
Many variables affect the optimum spindle speed
to use for any given operation, but the two most
important are the recommended cutting speed
for the workpiece material and the diameter of
the cutting tool, as noted in the formula shown in
Figure 48.
*
Recommended
Cutting Speed (FPM) x 12
Tool Dia. (in inches) x 3.14
*
Double if using carbide cutting tool
Figure 48. Spindle speed formula for milling.
Cutting speed, typically defined in feet per minute
(FPM), is the speed at which the edge of a tool
moves across the material surface.
A recommended cutting speed is an ideal speed
for cutting a type of material in order to produce
the desired finish and optimize tool life.
The books Machinery's Handbook or Machine
Shop Practice, and some internet sites, pro-
vide excellent recommendations for which cutting
speeds to use when calculating the spindle speed.
These sources also provide a wealth of additional
information about the variables that affect cutting
speed and they are a good educational resource.
Also, there are a large number of easy-to-use
spindle speed calculators that can be found on
the internet. These sources will help you take into
account the applicable variables in order to deter-
mine the best spindle speed for the operation.
Model G0808 (Mfd. Since 11/15)
Setting Spindle Speed
Use the chart below or the one on the headstock
when setting the spindle speed.
Change spindle speed range ONLY when the
spindle is completely stopped. Otherwise,
machine damage could occur.
To set spindle speed:
1.
Spindle
=
Speed
(RPM)
2.
Spindle Speed Range
0–350 RPM
0–2500 RPM
With spindle completely stopped, position
spindle speed range lever (see Figure 49) to
high or low ("H" or "L") range.
Note: If necessary, rotate the spindle by
hand to mesh the gears when changing
speed range.
Rotate spindle speed dial (see Figure 49)
to approximate desired spindle speed, then
turn machine ON. If necessary, adjust spindle
speed dial with machine running to fine-tune
spindle speed.
Spindle Speed
Dial
Figure 49. Spindle speed controls.
Range Lever
L
H
Spindle Speed
Range lever
-33-