STALEX C0632D, Operations Manual & Parts List

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Operation Manual
18
(1) Imperial leadscrew machines (Imperial threads only)
The table shows:
T.P.I: threads per inch to be cut.
Scale: the dial numbers at which the half nut of leadscrew may be engaged.
(2) Metric leadscrew machines (Metric thread only)
The table shows:
IN column 1: millimeter pitches to be cut.
28T, 30T, 32T: The number of teeth in
“
pitch-off gear
”
arranged to mesh with the
leadscrew (this being selected from the stack, stored on the bottom of the dial spindle)
Dial graduation:
The dial numbers at
which the half nut
may be engaged
under No. of teeth of
pick-off gear.
(3) Imperial threads on Metric leadscrew machines or Metric threads on Imperial lead
screw machines
For these threads the half nut is kept engaged throughout the cutting of any one
thread. This involves reversing the whole drive by means of the spindle control lever (17)
at each end of the thread cutting pass whilst at the same time relieving or increasing the
cut as required. (Threads
‘
A
’
may also be by this method)