Grizzly T25920 Lathe User Manual


 
Model T25920/T25926 (Mfd. Since 08/14)
-19 -
Adjusting Spindle
Speeds
A
B
C
= High Range
1600–3800 RPM
= Mid Range
1250–2800 RPM
= Low Range
650–1450 RPM
A
B
C
Spindle
Motor
(Viewed from Back of Headstock)
Figure 14. Speed ranges for each belt position.
Your lathe has three speed ranges for maximum
turning options. These ranges are selected by
changing belt positions on the motor and spindle
pulleys (see Figure 14).
High range (A) is best when turning a workpiece
where a clean finish is required and only light
cuts are made. Mid range (B) is a compromise
between the high and low ranges. Low range
(C), which has more torque, is best when turn-
ing a workpiece where a lot of material must be
removed and a rough finish does not matter. Use
the speed dial to adjust the spindle speed within
each range.
Refer to the speed recommendations chart in
Figure 15 to choose the appropriate RPM for your
operation. Then choose the speed range that will
include the selected RPM.
Always choose correct spindle speed for
your operation. Using wrong speed may lead
to workpiece breaking loose or being thrown
from lathe at a high rate of speed, causing
fatal or severe impact injuries.
To change speeds:
1. DISCONNECT MACHINE FROM POWER!
2. Loosen belt tension screw (see Figure 16).
Be sure belt tension lever moves freely to
release tension from belt.
3. Open side access cover and remove rear
access cover (see Figure 17).
Figure 17. Side and rear access covers.
Speed
Chart
Rear Access Cover
Removed
Side Access
Cover Opened
Figure 16. Belt tension lever.
Belt Tension Lever
Belt Tension Screw
Tool Needed:
Hex Wrench 6mm .............................................. 1
Diameter
of Work-
piece
Roughing
RPM
General
Cutting
RPM
Finishing
RPM
Under 2" 1520 3000 3000
2–4" 760 1600 2480
4–6" 510 1080 1650
6–8" 380 810 1240
8–10" 300 650 1000
10–12" 255 540 830
Figure 15. Speed recommendations.