The extension shafts on the South Bend lathe are too long for the purchased serpentine belt or for the old belt, so the extension will not lock in place. So a shorter version (shorter by about 1.5") of the rear extender was made.
An 8" length of 3/8" drill rod was cut off with a hacksaw. The end was faced, center drilled and chamfered. A thread relief groove (0.050") was cut at 1.5" with the cutoff tool. The machine was set up for threading and the 3/8-16 L.H. were started. The cuts were too much for the Sherline and were stopped at about 0.040" depth of the desired 0.047". A 1" diameter die was purchased from Grainger.
Unfortunately, none of the die holders in my inventory fit this size die so a die holder was made.
With the die holder in hand the left-hand threads were easily finished. The shaft was heated about 1" from the end with a propane torch. The hot shaft was placed in the vise. While holding the long end while wearing a leather glove the shaft was bent 90°. The shaft was fitted to the lathe, but since the curve was slightly larger than the original it needed to be bent more than 90° to get a good fit. This was done and now the extender works correctly.
