be clamped in the desired position by the tailstock
turn the spindle. The nose of the spindle holds the
clamping nut (13).
driving plate, the faceplate, or a chuck. The spindle is
hollow throughout its length so that bars or rods can
The dead center (11) is held in a tapered hole
be passed through it from the left and held in a chuck
(bored to a Morse taper) in the tailstock spindle (6).
at the nose. The chuck end of the spindle is bored to a
To move the spindle back and forth in the tailstock
Morse taper to receive the live center. The hollow
barrel for longitudinal adjustment, turn the handwheel
spindle also permits the use of the draw-in collet
(9) that turns the spindle-adjusting screw (7) in a
chuck, which is discussed later in this chapter. At the
tapped hole in the spindle at (8). The spindle is kept
other end of the spindle is the gear by which the
from revolving by a key (4) that fits a spline, or
spindle drives the feed and screw-cutting mechanism
keyway (5), cut along the bottom of the spindle as
through a gear train located on the left end of the
shown. After making the final adjustment, use the
lathe.
binding clamp (10) to lock the spindle in place.
The tailstock body is made in two parts. The
TAILSTOCK
bottom, or base (1), is fitted to the ways; the top (2)
can move laterally on its base. The lateral movement
can be closely adjusted by setscrews. Zero marks
inscribed on the base and top indicate the center
dead or ball bearing center or it can be used to hold
position and provide a way to measure setover for
tapered shank drills, reamers, and drill chucks. The
taper turning. Setover of the tailstock for taper
tailstock moves on the ways along the length of the
turning is described in a later chapter.
bed to accommodate work of varying lengths. It can
Figure 6-6.--Cross section of a tailstock.
6-5