I got myself an old Myford ML8 wood lathe and as with any old tool, there w as a bit of fettling to do before it was ready for work (well quite a lot, actually). Anyway, I eventually thought I was ready to begin turning, but w hen I pulled the tailstock clamp lever, it snapped off in my hand. On inspe ction, it seems that the previous owner had it screwed into the nearside of the clamp wheel, rather than running through it and screwing in to the far side; the former arrangement is pretty much bound to cause fatigue and ear ly failure, whereas the latter is correct and far more durable.
So, I am left needing to obtain threaded bar, or a blank bar plus a suitabl e die.
As best as I can measure on the stub of the broken handle, the fitting is 5 /16 inch, 28 threads per inch, which makes it a UNS thread. Now here is whe re I am confused: Tracey Tools sell a die at my measured specification (htt ps://www.tracytools.com/5-16-x-28-tpi), but ebay sellers seem only to be of fering 5/8 UNS 27 tpi. Can there really be a UNS 28tpi thread and a 27tpi?
The fact is that my measuring and extrapolating from a 1/4 inch stub means that I cannot be certain that 28tpi is the correct thread for my component, if 27tpi is a possibility.
A follow on question: if 5/8 UNS does indeed come in both 28tpi and 27tpi,w ould each fit the other satisfactorily over only around 1/4 inch of thread?
Thanks for any advice.