I'm currently tearing down and rebuilding my new to me 9" Southbend lathe. It had a lot of gunk in it, and a few missing or damaged parts. The only show stopper is the backing plate the HF chuck was mounted on. It was aluminum and apparently was either crooked as all hell to start with or got bent in the move. A good 1/8" runout. Since I have a pretty good supply of 5/8" thick steel available I'd like to make a back plate from it. The 4-jaw chuck is still usable despite the broken screws, so I'll use it to hold the plate and make the center hole. Then screw the plate on and finish it. But I've never done any internal threading before. What do I need, and how do I measure it? I could just cut the plate flat and then swipe the threaded bit from the back of the 4-jaw and screw the two together. But I'd rather have a one-piece plate. Actually, either way I go I suppose I'd have to have two pieces since my raw plate is 5/8 thick and I'd need a hub of some sort where it threads onto the spindle. Anneal the steel plate? It's the intermediate plate out of a 15.5" clutch, so the surfaces are probably work hardened to some degree. Plus having pieces of ceramic worked into the surface. Also, the step pulley around the spindle is gummy. How to clean it out? If I have to take it apart, how do I get it apart? Getting it apart would be handy anyway because then I'd have the option of putting an automotive belt on in place of what came with it. The current belt slips a lot at high speed and tends to jump out when the splice meets the slipping pulley.
- posted
17 years ago