[How-To] Southbend 9in Model A: how many teeth should all the drive gears have?

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Southbend 9in Model A: how many teeth should all the drive gears have? I saw a video about using the back gear and it showed different than what I have so now I am questioning all the gears.
 
Further info needed to answer your question; the back gears are not made to substitute other gears with different numbers of teeth, perhaps you are confusing the back gears with the feed/threading gear train? Better than Videos, find a copy of SBs book "how to run a lathe".
 
Sorry did not mean the back gear they had to extra gears to make the real course threads which I think they had a 40 tooth and a 22 tooth not positive of that but my extra ones were 32 tooth and I think 20 tooth. After seeing this I started questioning the number of teeth on the rest of the drive gears because if any of those are not correct none of my threading will be correct.
Thanks
 
I take it, that your machine does not have a quick change gearbox, if so, there should be a chart of all the gears required to cut threads and feeds that the machine is capable of, having owned both styles, I don't think that extra change gears can be used with a QC machine, I do not presently have a SB lathe of either style, so can't say for sure.
 
SB uses a 24 and 48 tooth stud gear on A models.
 
Yes it does have a quick change gearbox but if the other gears were altered then the gearbox will not work right. I am talking about the idler gear and the drive gear on the end of the gearbox and the ones for reversing the leadscrew. I am trying to determine if this machine has all the original gears or did someone change some or all of them.
 
Stud gear and screw gear are the only ones that matter, the rest just take up space.
 
Thank you for the help and I will check out the stud and screw gear. Now what about switching to the course thread the video used different screw gear than what I have.
 
Thanks for the guide, I learned some things but it still does not answer my question of. With the change gear box what tooth drive gears are on an original lathe. I am thinking that someone took a change gears (because they needed a replacement gear) from a change gear set and put it on a lathe with the change gear box. So are the original drive gears a 24 and 48 tooth?
 
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