chaser breakage to occur. This excessive end play
spindle and rotate it turn at a time, until a satisfactory
develops due to wear of component parts in the
reading is obtained.
(3) The correct vise screw end play is obtained through
the use of shims, Figure 11. To correct excessive end
play, the thickness of the shim between the vise screw
and handwheel should be reduced. A clearance of .003"
to .005" between the face of the handwheel retaining
washer and the machined face of the handwheel is
recommended to allow sufficient clearance and prevent
binding of the handwheel assembly.
(4) All carriage fronts must be centered with the die
head's center of rotation after an adjustment to the vise
screw has been made.
k. Air Operated Carriage Fronts
i. Die Head Removal
(1) The opening and closing of the vice jaws are effected
(1) Due to the size and weight of the die heads furnished
through two limit switches in conjunction with a cam. The
with 10C-20C Machines, it is recommended that an
limit switches are activated by a pin mounted in the limit
overhead crane be used to remove and replace the die
switch bar. These switches are easily accessible by
removing the limit switch box cover #405, Figure 22,
(2) Place a wide board across the carriage beneath the
die head as a safety precaution. Loop a rope, never use
(2) As the carriage moves forward from the loading
a chain, around the die head and pass one end through
position, a cam follower #335, Figure 22, Page 22, starts
the other and loop over crane hook. After the crane has
up the cam incline #345, Figure 22, Page 22, and closes
taken up the slack, loosen the yoke screw #2, Figure 13,
Page 15, and the head clamping screws. Jog the crane
the vise jaws.
Upon completion of the threading
operation, the vise jaws will open as the carnage returns
until die head is free of spindle.
to the loading position allowing the cam follower to
If an overhead crane is not accessible, the board placed
descend the cam incline.
beneath the die head may be used. Lift the board to
contact the underside of the head and loosen the yoke
(3) An adjustment to the amount of air being supplied to
screws and head clamping studs. For best results,
the vise jaws is made through the air pressure regulator
remove the head clamping studs in sequence-leaving the
#421, Figure 21, Page 21.
last stud at the uppermost position. As the last stud is
(4) In pipe and nipple threading or when cutting short bolt
removed, use the board to pivot the die head off the
thread lengths, it may be desirable to eliminate the
unnecessary travel of the carriage.
This can be
WARNING Due to the head's weight, extreme care should
accomplished by loosening the four screws in the cam
be taken in doing this.
bracket #344, Figure 22, Page 22, and re-positioning the
(4) When removing an Internal Trip Die Head from a 10C
cam in the bracket.
or 16C Pipe and Nipple Machine, unscrew the reamer
(5) It may also be desirable to limit the opening and
adjusting tube, and the clamping rod Figure 3, from the
closing stroke of the vise jaws. This is advantageous in
rear of the machine. Open the die head and remove the
high production pipe and nipple threading as the vise
jaws open only far enough to release the workpiece
j. Die Head Alignment
without letting it fall into the chip compartment. A blank
nipple is used to push the finished piece out of the grips
(1) When replacing a head removed for maintenance or
and simultaneously be gripped in the vise jaws.
cleaning, it must be checked for alignment with the
(6) To shorten the stroke of the grips, adjust the screw
spindle. Before mounting, Inspect the base of the head
and the spindle face for particles of dirt, bruises or burrs
located on the air cylinder until desired stroke is obtained.
as any of these conditions may result in an incorrect
(7) Additional adjustment to this screw will be necessary
reading. Fasten a dial indicator to the carnage and bring
when there is a change in diameter or when the grips are
the instrument into contact with the 0. D. of the die head.
replaced, turned, or sharpened.
After setting the indicator on zero, slowly rotate the
(8) When the machine Is equipped with an automatic
spindle and note the highest and lowest reading
workstop, the vise jaws should close just before the
recorded. The total indicator reading between the highest
workstop moves up from the gaging position and open
and lowest point must not exceed .005". If the indication
is not within the limits, remove the die head from the