ATS ULTIMATE CHUCK UC2, Installation, Operation And Maintenance Manual

Page: 29 / 44

ATS Systems Ultimate Chuck Installation and Operations Manual
RPM until 50% of the initial grip force remains, or you can weigh the master base jaw and top jaw
combination and make some simple calculations as shown in the manual section 4.4.
Demonstrate
how to remove the bolted together base and top jaw, to weigh it, to balance it in a knife edge to
determine and mark the center of gravity, to reinstall the jaw and measure the distance from
centerline to the CG of the jaw assembly when the jaw is in the proper position for the particular job,
and how to make the calculations by taking them either through their actual setup or examples #3
and #4 in the manual section 4.5.
Note that you can also use this technique and formulas to calculate the approximate safe speed of
standard chucks, but you must weigh and measure not only the top jaw but also the master jaw, bolts
and T-nuts as an assembly. If you don't include the master jaws you will calculate a speed that's way
too high. Of course, this requires you to disassemble the chuck which is impractical.
Are there any questions?
Now I want to talk about changing jaws, positioning jaws and bolting on jaws for safe operation.
- First, only use this special wrench to change jaws. A standard wrench will damage the chuck.
- Never leave the wrench in the chuck.. If you start the lathe, the wrench can fly out and hit you. If you
actuate the chuck with the wrench in, the chuck will be damaged.
- Only use jaw mounting bolts that are marked grade 12.9, with threads in new condition, and long
enough to engage a thread length 1 ½ - 2 times the diameter. Torque the bolts to the specification as
shown in the manual
(Chuck size 170-225 M8 18-24 ft-lb; 265-400 M12 60-80 ft lb; 500-630 M16
140-180 ft lb.) If you over torque, the base jaw may distort slightly and won't slide easily in the
guideway.
- Always position the inside end of the base jaw or monoblok jaw inside the "Safe" zone marked on the
face of the chuck. Don't ever extend base jaws beyond this limit, and don't ever position any top jaw
beyond the OD of the chuck more than a standard base jaw would extend when it is within the safe
zone.
Demonstrate installing a jaw, point to the safe zone.
- Finally on the subject of positioning jaws, always position the jaw to grip the workpiece as close
to the start of the jaw stroke as possible. The issue isn't that the chuck needs to operate near the
start of the stroke, the issue is that you want to have extra stroke available in case one of your
workpiece blanks is much smaller diameter than the blank you setup with. With the cylinder on
this lathe, this chuck has a jaw stroke of ___". The adjustment pitch is ___ ". The maximum jaw
stroke for this chuck is ___", so with this cylinder we are short stroking .....
(a little bit, a lot,
whatever describes this installation.)
UC2 Model 180 215 260 315 400 500 630
Adjustment .189 .189 .216 .216 .216 .275 .275
Max. Stroke .27 .31 .35 .36 .39 .45 .50
So when using hard jaws on this machine:
a. ( if the jaw stroke exceeds the adj. pitch more than .040") you might find two possible jaw positions
that work. If so, choose the one that grips close to the start of the stroke.