Grizzly G0755 Drill User Manual


 
Model G0755 (Mfg. Since 1/13)
-25-
Removing Tool Holder
Tools Needed Qty
Wrench 19mm ................................................... 1
Brass or Dead Blow Hammer ............................ 1
To remove tool holder:
1. DISCONNECT MACHINE FROM POWER!
2. Remove drawbar cap, and only unthread
drawbar from tool holder one full rotation.
Note: Do not fully unthread tool holder from
drawbar, or drawbar and tool holder threads
could be damaged during the next step.
3. Tap top of drawbar with hammer to unseat
taper.
4. Hold onto tool holder with one hand and fully
unthread drawbar with the other hand.
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 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 26.
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 Machinerys 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 26. Spindle speed formula for mill/drills.
Spindle Speed