I have a Jet 1442 and had to change a belt the other day... the change went smooth and everything back together and working fine... for a while... then suddenly, with a 12" bowl blank on the faceplate, the lathe went from 450 rpm to somewhere around 1200 rpm... that in and of itself was exciting...suddenly to have an out of balance propeller whirling in your face...
I opened the headstock to see what was the problem and discovered I had a slipped "C" or something that let the Reeves unit slip and jam against the housing.... since it was near the end of the day, I just left it for the next day, but it turned really cold for this area and I haven't been back to the shop for about 4 or 5 days..
This morning I went out to take a look.. it's still about 36 or 38 in the shop, but I have a new heater and decided I would try to fix the lathe... when I shined a light inside to take a better look, this is what I found.
I don't know how they got that grub screw out... gonna have to take away their allen wrenches I guess..
About 3 weeks ago, I discovered two or three caches of these in my big tool box.. in two different drawers... they probably knew this cold weather was on the way.