I'm gradually refurbishing the bits and pieces that came with my ancient Barnes lathe and I thought some readers might like to see this 1/2" capacity drill chuck made by the Union Mfg. Co. New Britain, Connecticut (Patented June 27. 1899). It was very rusty so I got to work on it using an angle grinder with twist knot brush. Then I took it apart, cleaned and oiled it - it operates nice and smoothly now. I was interested to see that the jaws are driven by right and left hand square screw threads (12 TPI) and there is hardly any backlash in the motion. I like to get these old things into usable condition.