Unimat SL Tailstock Lever Action Clamping Screws

[Paul Jones]

My 3” swing Unimat SL lathe uses M6-1 cap head socket screws for locking and clamping the tailstock. I replaced the M6 cap head socket screws with my version of clamping screws with swing-out levers to apply more torque. The swing-out levers eliminate using Allen wrenches.

The clamping screws were machined from 3/8” dia. 1018 CRS bar, the M6 threads cut with a tailstock mounted die, and the knurl is 21 pitch (whereby the 3/8” dia. was reduced to 0.364 before knurling). The swing out levers are 0.062” x 0.365” x 1.20” machined with 11/64” radii from 1/16” steel support rails salvaged from electronics rack panels. The slots in the clamping screw heads are 0.063” wide by 0.450” deep. The levers are retained with 3/32” roll pins shortened to fit.

More information and photos about the improvements to the Unimat SL lathe can be viewed at Homemade Lathe Modifications .