Connecting a vernier type DRO to drilling machine quill or tailstock mandrel

摘要

This month our lucky winner of £30 in Chester gift vouchers is Peter Sanderson, with an interesting application for small ball joints. To connect the slider on a Vernier- type DRO to the quill of a drill or to a lathe tailstock mandrel, I use ball & socket units normally used to connect model boat/aircraft servos to control surfaces. They are cheap (£1-£2 a pair) completely backlash-free, move easily and can be snapped apart without damage, if necessary. They make alignment easy and take up the rotational backlash of the quill or mandrel without putting any strain on the slider or fixed reader unit.