South Bend Tools SB1125, Руководство пользователя, Страница: 27 / 56

South Bend Tools
For Machines Mfd. Since 11/21 Model SB1125
-25-
O P E R A T I O N
Using the correct spindle speed is important
for safe and satisfactory results, as well as
maximizing 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 drive belt
on the appropriate speed range pulleys, and
3) adjust the spindle speed dial to produce the
required spindle speed.
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. Refer to
Calculating Spindle Speed Drilling on Page
27 for a guide.
The books Machinery’s Handbook or Machine
Shop Practice, and some internet sites, provide
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.
Cutting Speed (FPM) x 12
*
Recommended
Tool Dia. (in inches) x 3.14
=
Spindle
Speed
(RPM)
*
Double if using carbide cutting tool
Figure 29. Spindle speed formula. Figure 29. Spindle speed formula.
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 29.
The Model SB1125 has two speed ranges that
operate between 50–2000 RPM. The speed range
is determined by how the drive belt is installed
on the motor and center pulleys (see Figure 30).
Setting Spindle Speed
LOW
LOW: 50–400 RPM
Center Pulley
Motor Pulley
HIGH: 300–2000 RPM
HIGH
Center Pulley
Motor Pulley
The high-speed range is obtained when the drive
belt is positioned on the lower pulley sheaves,
and the low-speed range is obtained when the
drive belt is positioned on the upper pulley
sheaves, as shown in Figure 31.
Figure 30. Location of drive belt and speed pulleys. Figure 30. Location of drive belt and speed pulleys.
Figure 31. Belt configuration chart. Figure 31. Belt configuration chart.
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 determine the best spindle speed for the
operation.
Motor Pulley Motor Pulley
Center Pulley Center Pulley
Drive Belt Drive Belt