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Model G4000 (Mfg. Since 8/09)
the purpose of this subsection is to orient you
with the controls used when threading and how to
use the threading dial.
if you are unfamiliar with threading on a lathe, we
strongly recommend that you read books, review
industry trade magazines, or get formal training
before beginning any threading projects.
feed Lever
the feed lever must be in the disengaged (down
and horizontal) for threading operations or the
half-nut will not engage with the leadscrew (see
figure 56).
Threading Controls
figure 56. the feed lever in the disengaged
position.
Feed Lever disengaged
(down & horizontal)
Half-Nut Lever
the half-nut lever engages the carriage with the
leadscrew which moves the cutting tool along the
length of the workpiece (see
figure 57).
figure 57. half-nut lever engaged (down) for
threading operations.
half-nut Lever
Engaged (down)
Thread Dial & Chart
the numbers on the thread dial are used with
the thread dial chart to show when to engage the
half-nut during inch threading. the thread dial
gear must be engaged with the leadscrew for
this to work. Loosen the cap screw that secures
the thread dial, then pivot it so that the dial
gear meshes with the leadscrew, as shown in
figure 58.
figure 58. thread dial gear engaged with the
leadscrew.
Cap screw
thread dial gear
Leadscrew