Thread Dial - Grizzly G9972Z Owner's Manual

to use the thread chart, find the thread pitch per
inch (tpi) on the thread dial chart (see figure 49)
that you want to cut and reference the "dial" num-
ber next to it. the dial number(s) indicate when to
engage the half-nut when cutting that tpi.

THREAD DIAL

T.P.I.
8 10
12 14
15 18
20 22
24 26
28 30
36 38
40 44
46 48
52 56
9 11
13 19
23
9 / -11 /
1 1
2 2
figure 49. thread dial chart.
-36-
DIAL
1 – 8
2, 6
For example, to cut a tpi of 11, engage the half-
nut when the thread dial pointer is on 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 on
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 until
the threads are complete.
NOTICE
DO NOT engage the half-nut when the spin-
dle speed is over 300 RpM. Ignoring this
instruction could result in damage to the
leadscrew or carriage components.
G9972Z 11" x 26" Lathe w/Gearbox