# Threading question



## McGuyvers shop (Nov 17, 2012)

Hey, Got a simple question I think.  I've seen lathes with the thread dial and know that somehow you use it to tell when to engage the split nut starting the cut in the same place each time. My question is what is the procedure in threading when you don't have a thread dial?   My SB lathe doesn't appear to have a place to mount one, at least not where I've seen others (on the right side of the carriage) So how does one ensure the threads are correct without a thread dial??  Any help will be appreciated.  Thanks


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## Tony Wells (Nov 17, 2012)

Without a thread dial, you simply are restricted in that you cannot drop out of the half-nuts until you have a complete thread. You have to stop the spindle at the end of your thread, which can be a little awkward, and dial the tool out (or in if you are doing an ID thread) and reverse the spindle to start again, all without disengaging the half-nuts. There really should be a place to mount one if the lathe is able to cut threads. perhaps you just haven't spotted the place yet. When/if you do find it, you really should try to make or find one. Makes threading much simpler.


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## pjf134 (Nov 18, 2012)

I have heard of some SB Lathes not having a hole drilled for the dial, but you can drill a hole for it if you get one, they are about $100 most everywhere or just leave the half nuts engaged until you are done. The pic is of a 9A lathe with a thread dial on the apron for a reference to where it is.


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## McGuyvers shop (Nov 19, 2012)

I guess this is going to be part 2 of my threading dilemma. I've been noticing that the sliding gear hasn't been meshing well with one of the other gears, so after disassembling and cleaning everything well, I found that the previous owner made a "repair" to the gear bracket. The original one must have broken at some time so he welded a plate to the housing and mounted the gears to it.  A pretty good job, but the plate is warped so when it is tightened fully, it puts the gears in a bind.  I'll have to try to make a drawing of the bracket and see if I can make another solid one.  I contacted South bend lathe Co, and they told me that since my lathe was vintage (year 1939) there were no manuals or parts available for it.  So it is ebay, or make it myself.


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