When lining up a vice on a milling machine, where should the dial indicator be placed?

Placing the dial indicator on the quill or column of the milling machine is an effective method for accurately lining up a vice. The reason this positioning is beneficial is that the quill or column offers a fixed point from which to measure the alignment of the vice. When checking the alignment of the vice using the dial indicator, it’s essential that the reference point remains stable to ensure precision.

By using the quill or column, you can extend the indicator to touch the jaws of the vice, allowing you to determine if the vice is aligned correctly with the milling machine's spindle. This method assists in achieving the necessary precision for machining operations since any misalignment can lead to errors in the workpiece.

Other locations, such as the base or the bed of the machine, may not provide the same direct feedback regarding the vice's alignment with the spindle, while placing the indicator directly on the vice could lead to inaccuracies due to any slight movement of the vice itself during the setup process. Using the quill or column as a reference point is therefore the most reliable approach for ensuring that the vice is correctly aligned for precision milling tasks.