Grizzly G0793, Owner'S Manual

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Model G0793 (Mfd. Since 02/15)
7. Return spindle to up position.
Note:
Drill a hole into scrap stock before drill-
ing into any workpiece to ensure the depth
has been set correctly. If necessary, repeat
Steps 1–7.
Positioning Table
The table for this drill press moves vertically and
rotates 360 degrees around the column to accom-
modate larger workpieces.
Raising/Lowering Table
1. Remove all objects from table surface.
2. Loosen lock handles shown in Figure 21.
3 . Adjust table height by rotating height adjust-
ment crank (see
Figure 21).
1. Remove all objects from table surface.
2. Loosen lock handles (see Figure 21).
3. Push table to desired location, and guide rack
on side of column will follow.
4. Tighten lock handles.
Rotating Table
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 operation, and 2) configure the spindle
speed levers to produce 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 22.
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.
Cutting Speed (FPM) x 12
*
Recommended
Tool Dia. (in inches) x 3.14
=
Spindle
Speed
(RPM)
*
Double if using carbide cutting tool
Figure 22. Spindle speed formula for mill/drills.
Spindle Speed
Figure 21. Location of column lock handles and
height adjustment crank.
Height
Adjustment
Crank
Lock
Handles