On a bigger scale I have a ten inch rotery and it has a #3 moris in the center I took a discarded Drill and ground the drill to a comon size in my od grinder then cut it off and fasioned a bushing to fit it and the Id. of my ten" three jaw this makes swaping it around easy drilled the mounting holes through and counterboard for allen's and it can be on the rotery or a back plate for the lathe A 4" three jay inport is only about $50.00 From enco or MSC to save the grinding op you could use a drill chuck adapter or fassion a tapered dowel Carry on Kevin |