Headstock Disassembly

Post date: Feb 19, 2012 1:05:52 AM

I tackled this today. Disassembled the headstock and cleaned most of the small parts using mineral spirits. LOTS of grime!

Some pics and notes:

One thing I discovered is that this lathe does in fact have a power feed. That's what the three gears to the far left are for; there is a small lever to the right of those gears that engage the power feed. An experienced machinist would have figured this out immediately. I'm not one of those. (Originally, before I'd had time to investigate, I thought those gears were simply stored on the side and were manually swapped out with the main gears to change speeds.)

I don't have a good picture of it, but the 3-way V-belt pulley on the main shaft is neither press-fit nor keyed to the shaft. It actually would, normally, free rotate around the shaft. It is, however, bolted directly to the larger gear to its right, and done so in a way that further confirms my hunch the V-belt drive system was added later. Update: turns out, this is original. The bolt allows the pulley and main gear to be engage/disengaged from each other as part of a larger system for changing gear ratios.

Left side of the headstock, showing the power feed gears. At the upper left is a gear that, I'm guessing, is intended to change speeds of the lathe. That gear's shaft has non-centered pins on each each end such that the shaft (and the two gears on it, one of which is hiding behind the big one) can move a little closer to the main shaft gears. (Another thought is that this was the original "clutch", for lack of a better term, for engaging the main shaft, in which case it is useless to me.) Update: this is called a "back gear" and is used for changing gear ratios. When the back gear is engaged, the "slipping" design of the belt pulley allows for driving the pulley at one speed, which turns the back pulley, which then turns the larger gear on the spindle at a different speed than the pulley. What I thought was a hack to attach the pulley to the main gear is actually a way to engage/disengage it from the main gear. Wicked!

Shot of the main shaft and clutch (?) shaft with the top cover removed (the part askew to the right). The clutch's shaft had to be tapped out with a pin punch before the main shaft could be removed. Note that the main shaft runs inside a brass bushing, not a bearing. Is this another sign of advanced age, or is this typical of lathes in this size? I confess I'm surprised by this.