To achieve the .0005" radial runout and repeatability, it's required to use the 4 micro adjustment set screws to true the designated ground bar stock, not the chuck body. Do not attempt to put the indicator on the outside diameter of the chuck body to dial it to zero first as this would create more runout on the bar stock. The adjustable chuck is intended to give high repeatability clamping on a particular bar stock size after the set screw adjustment. After the adjustment is made on a particular bar stock rod, for example 1/2", it's required to true the bar stock again when clamping a different size diameter, for example 1". Please refer to the back plate machine guide pdf file for more mounting instructions.
Semi-steel chuck body made from high quality cast iron
1 pinion design with each pinion ground and hardened to HRC 43
Two piece jaw design with a master jaw and a top reversible jaw in American Standard tongue and groove specification
Both side of jaw teeth and guides are ground and hardened to HRC 58-62
Each set of jaws are serialized in their own set
A serialized set of jaws are then finished, ground, and lapped on their designated chuck body which will be the same chuck body on the final assembly to achieve a greater accuracy
Before assembling the jaw to its designated chuck body, the jaw's finish machining are performed on a closed tolerance state of the art CNC machine from Japan
Scroll plate's thread flank are ground on both side to achieve a tighter contact with the master jaw
Each chuck has gone through rigorous accuracy and repeatability inspection with clamping and jamming multiple random testing rods or rings
Chuck Diameter
5" min-max
6" min-max
8" min-max
10" min-max
12" min-max
15" min-max
A1
.1181-1.9685
.1181-2.5200
.1575-3.5433
.1969-4.4657
.3937-5.1575
.3937-7.0866
A2
.1339-2.9921
1.6142-3.8189
2.2835-5.1181
2.7165-6.4961
3.2283-7.1654
4.2520-11.3386
A3
2.9527-4.6457
3.4252-5.7480
4.3307-7.4803
5.3937-9.7638
6.4961-10.4331
7.4409-12.9528
A4
2.0472-3.7795
2.4409-4.7638
2.5197-6.1417
3.0315-7.0866
3.5433-8.8976
4.1732-11.3386
A5
3.7402-4.9213
4.5276-6.2992
4.8819-7.8740
5.7874-9.8425
7.0866-12.4016
7.4409-14.9606
What’s Included
1 set of reversible jaws for inside and outside
6 piece of mounting screws for the lathe chuck back plate