Machinery Repairman

adjustments provided, you can increase or decrease the
length of stroke of the ram. You also can position the
ram so the stroke is in the proper area in relation to the
work.
You can adjust the CRANKPIN, which is mounted
on the crank gear, from the center of the crank gear
outward. The sliding block fits over the crankpin and
has a freesliding fit in the rocker arm. If you center the
crankpin (and therefore the sliding block) on the axis of
the crank gear, the rocker arm will not move when the
crank gear turns. But, if you set the crankpin off center
by turning the stroke adjusting screw, any motion of the
crank gear will cause the rocker arm to move. This
motion is transferred to the ram through the ram linkage
and starts the reciprocating motion of the ram. The
distance the crankpin is set off center determines the
length of stroke of the tool.
Figure 9-1.—Standard shaper.
9-2
To position the ram, turn the ram positioning screw
until the ram is placed properly with respect to the work
Specific procedures for positioning the ram and setting
the stroke are in the manufacturer’s technical manual
for the specific machines you are using.
CROSSRAIL ASSEMBLY.—The crossrail
assembly includes the crossrail, the crossfeed screw, the
table, and the table support bracket (foot). (See fig. 9-1.)
The crossrail slides on the vertical ways on the front of
the shaper column. The crossrail apron (to which the
worktable is secured) slides on horizontal ways on the
crossrail. The crossfeed screw engages in a mating nut,
which is secured to the back of the apron. You can turn
the screw either manually or by power to move the table
horizontally.