Limited production runs (usually less than 250
pieces) are sometimes produced on a manually-
operated turret lathe, Figures 28-29 and 28-30. A
turret lathe is equipped with a six-sided tool holder
called a turret, to which a number of different
cutting tools are fitted. Stops control the length of
tool travel and rotate the turret to bring the next
cutting tool into position.
A cross-slide unit is fitted for turning, facing,
forming, and cutoff operations.
The automatic screw machine, Figure 28-31,
is another variation of the basic lathe. It was
developed for the high-speed production of large
numbers of small parts. The machine performs a
maximum number of operations, either simulta-
neously or in a very rapid sequence.
Work too large or too heavy to be turned in a
horizontal position is machined on a vertical
boring machine, Figure 28-32. These huge
machines are capable of turning and boring work
with diameters up to 40′ (12 m) in diameter.
Conventional lathes are manufactured in
sizes ranging from tiny jeweler’s lathes to lathes
that turn forming rolls for the steel industry,
Figure 28-33.
458 Modern Metalworking
Figure 28-28.
The Hardinge Super Precision HLV-DR toolroom
lathe. (Hardinge Super Precision HLV-DR is a
registered trademark of Hardinge, Inc.)
Figure 28-29.
A manually-operated turret lathe. (Clausing
Industrial, Inc.)
Figure 28-30.
A large more versatile turret lathe. It has power feed
for all functions controlled by preset stops.
(The Warner & Swasey Co.)
Figure 28-31.
The automatic multiple spindle screw machine is
used for precision high speed production.
(The Warner & Swasey Co.)