Maximum Accuracy and Repeatability:
Bore out to a dimension .001"
Greater Than
the
O.D. of the workpiece.
Maximum Holding Power:
Bore out to a dimension .001" to
.002"
Less Than
the O.D. of the
workpiece.
When a stepped type bore is required,
finish bore to the
proper size and then face the bottom of the bore to provide a square
shoulder. It is recommended that the corner where the bore and
shoulder meet be undercut to insure that the workpiece fully seats
against the face of the step.
•
Using the Illustration as a guide for Maximum Diameters and Depths, Drill, Rough Bore and then Finish Bore the Step
Chuck out to the proper size for the workpiece.
1-1/8"
Stop
Rod
Nut
S
t
op
Bo
dy
1/2"-20
TPI
•
The
Stop Rod
is set at a 1-1/8" dimension from the face of the Stop
Body. The
Stop Rod
can be machined to decrease its length.
Custom
Stop Rod Extensions
can be made that are threaded into
the
1/2"-20
TPI
internal thread in the
Stop Rod
.
•
Remove the
Dead-Length Step Chuck Assembly
from the spindle and thoroughly clean out chips from the slots
and the bore. Debur the edges of the machined surfaces.
BORING OUT
(Continued)
•
Draw the assembly into the spindle by adjusting the collet closer draw tube until the back face of the Step
Chuck just contacts the face of the spindle. A very noticeable increase in resistance will be felt at this point.
•
Further tighten the draw tube 1/2 turn and then continue turning until the next screw hole lines up.
•
Tighten the Screws on the collet closer.
•
Make certain that the three 1/8" Diameter pins are fully bottomed in the Dead-Length Step Chuck.
CAUTION: Do not actuate the lathe's collet closer without either the three pins in the face of the Dead-
Length Step Chuck or a workpiece in place. If the unit is closed without the pins or workpiece
in place, both the Dead-Length Step Chuck and the Outer Collet will be permanently distorted
and have to be replaced.
•
Close the Step chuck using a low to moderate chucking force, approximately 3000 Lbs.
3-1/2"
1-3/4"
.
250
.5
3-1/2"
1-1/8"
