It is common practice to place some packing between one of the jaws of a 3 jaw chuck in order to turn an eccentric feature. For those cases where precision is necessary, software tools are available to define the precise packing needed. For the rest of the cases, the accuracy achieved with a spud and a set of scribed marks is fine. The 3 jaw chuck attachment presented here is for this lower accuracy case.
If you are interested, please see
Your comments are welcome. All of us are smarter than any one of us.