13
The numbers in the “SCALE” column refer to the numbers
on the radial lines on the Indicator Dial. Therefore, if a 20
TPI thread is to be cut for example the marks 1, 3, 5 or 7
may be used. You should proceed as follows:
1. Observe the spinning Dial. In particular, concentrate on
one of the numbered marks etched in the dial which corr-
responds to the scale number given in the Indicator
Table. (In our example, this could be, 1, 3, 5 or 7).
As your line passes the mark on the body of the dial indi-
cator, engage the auto lever sharply and thread cutting
will commence.
2. As the tool approaches the end of the desired thread, DIS-
ENGAGE THE AUTO FEED LEVER. Do not switch the
machine OFF.
3. Retract the tool, using the cross-slide feed handle, noting
the exact position on the scale and the exact number of
turns.
Crank the saddle back to the beginning and reset the tool
by cranking IN the cross-slide the exact number of turns
previously wound OUT and then continue to crank IN to
the desired depth ouf cut.
4. With the machine still running, observe the dial indicator
and, as the same numbered line, passes the mark on the
body, engage the auto feed lever once again. Proceed in
this manner until the thread is completed.
Engaging the auto feed lever as your predetermined line
on the dial passes the mark on the body ensures the half
nuts of the auto feed mechanism engage in the same
place for each pass, which in turn produces a perfect
thread.
INDICATOR TABLE
