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Copyright © 2021 Quality Machine Tools, LLC
PM-1340GT v8 2021-04
Figure A3
Headstock attachment screws, LH
Remove the large transposing gears for better access to
these screws.
Figure A4
Adjustment screws below the headstock
The recessed socket head screw C locks the adjustment by
pulling the tab rail toward the lathe bed. Loosen C a fraction
before touching A or B.
PM-1340 HEADSTOCK ALIGNMENT
Figure A1 is an exaggerated view of what happens if
the spindle is not precisely aligned with the lathe bed.
This is correctable by
slightly
loosening the attachment
screws, Figures A2 and A3, then adjusting the screws
set into a tab rail below the headstock, Figure A4.
CAUTION!
Correcting hea
dstock misalignment is a multi-step pro
-
cess requiring a number of
extremely small adjust-
ments
, each one followed by an alignment test, either
cut-and-try, or one of the other methods described pre-
viously.
A scarcely detectable rotation of an adjusting screw
can be the difference between perfect alignment and
unacceptable taper
. In other words, think in terms of
thousandths of an inch or less. Simply loosening C, the
center socket head, can be enough to correct a taper
problem — or add to it in the wrong direction.
Figure A3
Misaligned headstock
In this illustration the workpiece diameter increases as the cut-
ting tool moves toward the chuck. Correct this by screwing in
(A) a fraction of a turn to rotate the headstock counter clock-
wise, moving the workpiece away from the tool. Screw in (B)
if the taper is in the other direction, thinner toward the chuck.
Figure A2
Headstock attachment screws, RH
