Thread Selection
Inch thread selection:
To cut threads with inch pitches, a selection must be made for feed direction, pitch and lead screw.
Select the desired direction of cut as described in the section titled Feed Direction.
Rotate the Feed/Lead Screw selection lever to the position shown in Figure 14. If the lever does not readily engage, rotate the lead screw or the chuck by hand while maintaining gentle pressure on the lever.
Figure 14. Selector positioned for threads.
While other thread pitches may be achieved, the G4002/3 comes with a chart that requires no gear changes for cutting inch threads.
To achieve a desired thread pitch in inches, it is necessary to determine the quick-change lever positions. Refer to Figure 15 and find the desired thread.
Example:
The thread to be cut has 20 threads per inch (TPI). Looking at the chart we find that the left hand lever would be positioned at “C”. The right hand lever would be positioned at “4”.
Figure 15. Thread pitch chart.
G4002/3 Gear Head Lathes |