-28-
G4003G Gunsmith's Lathe
The chart is divided into 3 main columns. Starting
from the left: Gear diagram, Combination of Gears
and
m
/m Per Pitch.
To use the chart:
1.
Find the desired pitch in the chart
(Figure
34)
.
This lathe can cut 29 different metric threads, but
gear changes are required to cut all of the listed
metric threads. These gear changes take place on
the left hand end of the machin
e (Figure 33).
Change Gears and
Metric Threading
Figure 34. Metric thread chart.
Figure 33. Change gear locations.
91-Teeth
F
86-Teeth
G
2. Below the
m
/m Per Pitch label are numbers.
Find the corresponding number above the
desired pitch and change the right hand quick
change lever to that position.
3. To the left of the desired pitch is a small col-
umn with a letter. This letter indicates place
-
ment of the left hand quick change lever.
Move the lever to the corresponding loca
-
tion.
4. In the “Combination of Gears” column are 3
small columns. Please note the
F and G at
the top. The numbers below
F and G repre-
sent the number of gear teeth on a change
gear. Find the required change gears that
have the corresponding number of teeth as
stated in the chart to the left of the desired
pitch.
