Cutting rads on a rotary table the easy way.

[Mook]

If you use a rotary table often it may be worthwhile to add a tenon on the base for a simple pre-trammed setup in the vise.
Making a couple of precision tenons & clamps to use with a grinding vise makes setting the setting of radius centre points easy.
Using the tool shank, a pin or even the spindle nose makes setting an endstop simple.