Fully machined back plate can be directly mounted onto our 5" 5C zero set adjustment collet chuck.
Bolt circle diameter: 4.25"
Adapter boss diameter: 3.74"
Adapter boss height: 0.69"
A light skim cut is required on the adapter boss OD and the face of the adapter's contact area. The clerance between adapter boss OD and the chuck counterbore ID should be from 0.0078" to 0.0129". The adapter boss nose should not be in contact with the bottom of the chuck counterbore. The gap between the adapter boss and the bottom of the counterbore should be around 0.0787".