(2) Adjustment for pitch diameter. The diestock (fig 33) for holding round
split open adjusting dies (fig 32) has three screws. A fine pitch screw in this
diestock enters the split in the die and forces the sides apart and the other two
screws are on the opposite side for compressing. A single screw diestock (fig 33)
is used to hold dies of the round split screw adjusting type (fig 32), that are
provided with an adjusting screw which forces the sides apart or allows them to
spring together, although this type die will fit in a three-screw diestock as well.
Two-piece rectangular dies (fig 32) are adjusted by setscrews at either end of the
diestock or of the slot in the collet (fig 33 and 34) in which they are placed.
(3) Threading pipe.
The procedure for threading pipe is as described below.
(a) Lock the pipe securely in a pipe vise (fig 40).
(b) Inspect the dies to see that they are sharp and free from nicks.
(c) Assemble two-piece rectangular pipe die (fig 32) on adjustable die
guide and ratchet diestock (fig 34).
(d) Set the die to the desired size.
(e) Apply cutting oil to cutting edges of die and to the pipe to prevent
overheating of dies and marring of the cut threads.
(f) Place diestock on the pipe and push lightly with the heel of your
hand until the die is up against the end of the pipe. Adjust guide to admit pipe
by loosening thumbscrew (fig 34), rotate cam plate until guide fits pipe, and
tighten thumbscrew after adjustment.