Smithy MI-1440L, Руководство оператора, Страница: 33 / 62

CHAPTER 10
Threading operation
Overview
This lathe is capable of cutting imperial or metric
threads. There are gears on the end of the
machine under the belt cover that will need to be
changed for cutting some metric threads.
Half Nut Lever
This lever compresses and releases the half nut that engages the leadscrew.
The half nut is used only when cutting threads. There is a lockout that
prevents the half nut from being engaged when the powerfeed is engaged
for cutting.
Threading dial
The indicator tells you when to engage the
half nut to begin the threading
process. The housing of the threading dial
must be loosened and the entire assembly
rotated so the gear on the
end of the thread dial contacts the feed
screw. The dial will turn as long as the half
nut lever is up and the feed screw
is turning.
There is a reference mark on the threading dial housing and numbers on the
dial. When the half nut is engaged the dial stops turning. By carefully
engaging the half nut as the appropriate line or number passes by the
indicator mark, a thread can be established and the lead maintained through
the multiple passes that are required to cut a thread to the finished depth.
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