G'day.

In another thread I was asked how I made a set of small soft jaws. I required them to hold a Cox Tee-Dee .049 backplate so that it could be drilled and tapped to hold an 8BA threaded rod.

I cut three axial slits (Junior hacksaw) in a piece of round aluminium bar. One slit was continued almost to the centre, the other two a few mm short of the intended bore size.

The deep slit was packed with scraps of aluminium drink can and when mounted in the 3 jaw chuck the compression held everything tightly in place. #1 jaw location was marked (just in case it moved).

A hole was then drilled and bored so that the unthreaded part of the backplate was a snug fit. Then the chuck jaws were slightly loosened so that the ends of the packing could be pulled out, the backplate inserted and when the chuck was tightened the backplate was firmly held.

This is actually an adaptation of the method that I use to make small piston adjustable laps, the only difference is that the OD is first turned to fit into a die holder.

* Danny M *