Precision matthews PM-1440GS, Руководство пользователя

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Copyright © 2020 Quality Machine Tools, LLC PM-1440GS v3 2020-10
GIB ADJUSTMENT
Gibs on the cross slide and compound are gently-tapered
lengths of ground cast iron held fast by opposing screws at
each end (Figure 4-9 shows only the screw facing the hand -
wheel). Adjusting them is a trial and error process that takes
time and patience. Aim for the best compromise of rigidity and
reasonably free table movement. Too tight means accelerated
wear on the ways and leadscrews. Too free means instability
of the cutting tool, inaccuracies and chatter.
Both screw heads must be tight against the gib ends. If you
loosen one, tighten the other.
The carriage , Figure 4-10, is not a tapered insert like those
on the cross slide and compound. It is a three-part assem-
bly on the underside of the bed way at the back of the lathe.
It comprises a support bar, attached to the carriage, and two
separate gib strips each with two adjusting screws.
Figure 4-8 Tailstock oilers
Figure 4-10 Saddle gib at back (representative)
Figure 4-9 Cross slide and compound front gib screws
SPLIT NUT ADJUSTMENT
In screw-cutting operations, if the split nut becomes exces-
sively loose — appreciable side to side movement — this may
be corrected by adjusting the gib at the right side of the apron.
Remove the threading dial. Loosen the locknuts securing the
three screws in Figure 4-11, tighten the screws as necessary,
then re-lock.
Figure 4-7 Leadscrew and feed shaft oilers
Leadscrew oiler at
headstock end
Figure 4-11 Split nut gib screws
Oilers that are easy to forget ...
Remove the belt cover left of the headstock for access
to the external change gears. There are ball oilers on the
two intermediate gear spindles.