LATHE OPERATIONS - OD1645 - LESSON 1/TASK 1
dovetail and the matching dovetail of the crossfeed slide. The gib permits
small adjustments to remove any looseness between the two parts. The slide
is securely bolted to the crossfeed nut which moves back and forth when the
crossfeed screw is turned by the handle.
crossfeed handle is graduated to permit accurate feed.
Depending on the
manufacturer of the lathe, the dial may be graduated so that each division
represents a 1 to 1 ratio.
The compound rest is mounted on top of the
(c) The carriage has T-slots or tapped holes for clamping work for
boring or milling operations. When the lathe is used in this manner, the
carriage movement feeds the work to the cutting tool which is revolved by
the headstock spindle.
(d) The carriage can be locked in any position on the bed by tightening
the carriage clamp screw.
The clamp screw is to be used only when doing
work for which longitudinal feed is not required, such as facing or cutting-
off stock. Normally, the carriage clamp is kept in the released position.
The carriage is always moved by hand to make sure that it is free before the
automatic feed is applied.
(6) Apron. The apron (figure 2 on page 5) is attached to the front of the
It contains the mechanism that controls the movement of the
carriage for longitudinal feed and thread cutting. It controls the lateral
movement of the cross-slide.
One should thoroughly understand the
construction and operation of the apron before attempting to operate the
lathe. In general, a lathe apron contains the following mechanical parts:
(a) A longitudinal feed handwheel for moving the carriage by hand along
the bed. This handwheel turns a pinion that meshes with a rack gear that is
secured to the lathe bed.
These gear trains transmit
power from the feed rod to move the carriage along the ways and to move the
cross-slide across the ways, thus providing powered longitudinal feed and