"half" tailstock

As I don't have a lathe, I have to make do with my Wabeco drill stand with cross table. I recently had to drill an axial hole in a 10 mm steel axle and cut an M6 thread. The lathe has a tailstock with a drill chuck for this. So here is the design for one, but without a "feed" - hence the "half" tailstock. I use the cross table for the feed. You also need a drill chuck with an SDS holder, which is pressed into the tailstock. The hexagon (SW17) absorbs the torque (as long as it is not too m