Thread Dial - Grizzly G4000 Owner's Manual

to use the thread dial chart (see figure 59), find
the tpi (threads per inch) on the chart that you
want to cut, then reference the dial number to
the right of it. the dial numbers indicate when to
engage the half-nut for a specific thread pitch.
Note: The thread dial chart can also be found on
the front of the change gear door.

THREAD DIAL

T. P. I.
8 10
12 14
16 18
20 22
24 26
26 30
36 36
40 44
46 48
52 56
9 11
13 19
23
1 1
9
11
–
2
2
figure 59. thread dial chart.
Model G4000 (Mfg. Since 8/09)
DIAL
1 – 8
1, 3
5, 7
2, 6
For example, to cut a tpi of 11, engage the half-
nut when the thread dial points to the 1, 3, 5, or
7. to cut a tpi of 24, engage the half-nut on any
number between 1 and 8.
to maintain accuracy and consistency, engage
the half-nut on the same thread dial number for
each pass. Failure to start on the same number
each time may lead to cutting off the thread made
in the previous pass.
Note: The thread dial is not used when cutting
metric threads. Leave the half-nut engaged from
the beginning until the threads are complete.
NOTICE
DO NOT engage the half-nut when the
spindle speed is over 300 RpM. Otherwise,
damage to the leadscrew or carriage com-
ponents could occur.
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