I am wondering if there is a misunderstanding here.
I believe xk is asking how to set up the machine.
Lets say you want to hold your part in a vise.
First you bolt the vise to the table and when in the process of tightening the bolts you need to tram (with a test indicator) the face of the fixed jaw true to the table ways.
When complete clamp in your workpiece & (depending on accuracy required) you would normally edge find the X0, Y0 part edges and set those coordinates as your fixture offset.
Hope this helps; if I misunderstood the question please disregard.
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