Small rotary table

[threesixesinarow]

This is a rotary table I made to use on my small Atlas horizontal mill. It’s a one-third size imitation of an old Bridgeport accessory but uses steel plate and a plain bearing instead of castings and roller bearings.

Like the Bridgeport it’s very low compared to its diameter, and like it, and I think old South Bends it pivots the worm to rotate the table freely. A pair of clamps lock the table in place and can be set to drag a little for milling things like grooves.

It’s about 6-1/4” square and 1-9/16” high. The table is 5-1/2” diameter with four 5/16” slots for standard 1/4” t-slot nuts. The worm drive is 90:1, with a zero-adjustable dial marked in 0.1 degree increments.

The body and hub are mild steel, but the table is from some harder scrap. The spindle is turned down from an old Morse taper adapter, and the main bearing and worm gear are bronze.



Side view, and comparison with the Marvin rotary table marketed for use with Atlas mills



With my 2” vise, and gashing the worm gear