This a Burke Model D2, Serial #6877 hand/production mill that I converted to a lead screw. It is a 40 taper machine with a fairly new 2 HP 3 Ph. motor. It has a Dodge speed reducer that by swapping the 2 4-step pulleys between the motor, back gear and direct drive give 16 speeds from 50-3100 RPM.

The only modification I had to make to the mill itself was to mill a short section out of underneath of the table to give clearance to the Acme nut and drill & tap some holes.
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Jon Bohlander