Grizzly G0791, Owner'S Manual

Page: 65 / 132

Model G0791 (Mfd. Since 9/15)
-63-
The following examples explain how to use
the thread dial and the thread dial chart.
Even TPI: For threading an even number TPI,
use any numbered line on the thread dial (see the
example in
Figure 94).
1
2
3
4
1
2
3
4
1
2
3
4
SCALE
1–8
SCALE
1
SCALE
1, 3
1
2
3
4
SCALE
ANY
1
2
3
4
SCALE
1-2-3-4
1–8
&
Figure 94. Any numbered line on dial for
threading even TPI.
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
SCALE
ALL
SCALE
N
SCALE
1
SCALE
1, 3
1
2
3
4
SCALE
ANY
Figure 95. 1 or 3 line on dial for threading odd
TPI.
Odd TPI: For threading an odd number TPI, use
any pair of opposite numbers or marks on the
thread dial (see the example in
Figure 95).
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
SCALE
ALL
SCALE
N
SCALE
1
SCALE
1, 3
1
2
3
4
SCALE
ANY
Figure 96. 1 line on dial for threading fractional
TPI.
Fractional TPI: For threading a fractional TPI with
a half number (4.5, 5.5, 6.5, 9.5), only use the
1
line on the thread dial (see the example in
Figure
96).
Important: For cutting 4.75 TPI, proceed as
though cutting a metric thread and do not disen-
gage the half nut until the threading operation is
complete. Stop the spindle at the end of each cut,
retract the cutting tool, and reverse the spindle to
return the cutting tool to the start of the thread.
Note: For TPI divisible by 4, this rule still applies.
The Indicator Table on the lathe shows that lines
1–8 may be used, which means that lines 1–4 and
any of the half marks may be used.