ATS ULTIMATE CHUCK UC2, Installation, Operation And Maintenance Manual

Page: 19 / 44

ATS Systems Ultimate Chuck Installation and Operations Manual
WARNING
It is essential to observe this jaw position to
ensure that all teeth are interlocked for power
transmission from the wedge bars to the base
jaws. Never position jaws out past this limit.
Fig 4.1
4.3 Use half-pitch base jaws when required. See
this manual section 3.1.2
If your actual jaw stroke is less than .050" longer than
the jaw adjustment pitch and you are using hard jaws
and the adjustability feature of the chuck to grip
different diameters, use half-pitch base jaws as
required. Half-pitch base jaws look like standard base
jaws except the position of the groove on the top of the
base jaw that mates with the tongue on the bottom of the
top-jaw is offset from the gear-rack by 1/2 the pitch of the
gear-rack teeth. Use 1/2 pitch or standard base jaws as
required to grip the diameter you need and allow each jaw
to have at least .050" of residual travel after the part is
gripped. Be sure your lathe's stroke control system is
properly adjusted in case the chuck reaches the end of the
jaw stroke without actually securily gripping the
workpiece.
4.4 Bolting top jaws to base jaws
Torque top jaw to base jaw mounting bolts to the
following specifications. Over tightening these bolts can
distort the base jaw and cause them to bind in the jaw
guideway. Under tightening could allow the top jaw to
come loose from base jaw.
M8 18-24 ft-lb M12 60-80 ft-
lb
M16 140-180 ft-lb
ATTENTION
Never tighten jaw mounting bolts with a wrench
extension (cheater bar) or by striking the wrench
with a hammer! This can damage the bolts and lead
to bolt failure.
4.5 Top Jaw Concentricity
For best chucking concentricity, soft jaws must be bored
in the chuck while gripping on a plug or ring with the
same clamping force that will be used for the workpiece.
•
When boring the jaws it is important that the
boring ring or plug is clamped by the top jaws and
not by the base jaws.