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Help newbie understanding quick change gearbox brass tag.


May 12, 2019
Hello all. I am new to lathes and just bought my first “real” lathe a month ago. I got a 1953 Logan 1922 which is an 11” lathe. I am trying my hand at threading and I cut my first set today and I am happy to report it was mildly successful. They turned out very nicely. However I am having a hard time understanding the brass tag on the gearbox… for instance, if I wanted to cut a 14 TPI thread, my left “gear shifter” should be in the “A” slot, but there is another gear shifter on the right of that one and I don’t see any indication on the brass tag to tell me what that is used for. Ive looked all over YouTube with no success. Can anyone explain to me how to understand this tag on the gearbox? Thank you so much!

Bill D

Apr 1, 2004
Modesto, CA USA
If it is like the one in this picture left lever is in column A. The right lever is in the column clear to the right. Gives you 14 tpi. Move the right lever one place to the left and it is 13 tpi. Move it to the second from right column gives you 12 TPI. etc.
Kind of like reading a times table in math class.
Bill D


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