Rotary table magic

摘要

To precisely locate a circular part or feature on a rotary table, a machinist must do two things. First, he must position the part over the rotary table's true axis by spinning the table and carefully "bumping in" the workpiece while watching the indicator readings. When the needle stops deflecting or reads zero, the workpiccc's axis is directly over the rotary table's axis. The indicator does not have to be mounted in the machine spindle, but it can be. Second, a machinist must position the milling machine's spindle directly over the axis of the workpiece. He does that by spinning the indicator around the workpiece and adjusting the X and Y tables of the machine until the indicator reading doesn't change or reads zero. To accomplish this task, the indicator must be mounted in the spindle.