thread measurements 13/4X8 T.P.I.

[lathe nut]

Guys, I did give a response and clicked on Reply and it went into outer space, do the make a die that would fit that thread on the dividing head, I think it is a 39mm X4mm or a 40mm you guys know more about that than this American boy does, I did find out that the was made by the Trans-Acc. company, it was a division of Carroll, I think the last ones were made in the 1950's, really don't get why metric, if all else don't work out I can always get a machine shop to cut it down to 1 1/2" X 8 threads that way I can switch from it to the Atlas, Logan lathe, my thinking which could be wrong., thanks for the help fellows, Joe

 

[lathe nut]

Guys, I did give a response and clicked on Reply and it went into outer space, do the make a die that would fit that thread on the dividing head, I think it is a 39mm X4mm or a 40mm you guys know more about that than this American boy does, I did find out that the was made by the Trans-Acc. company, it was a division of Carroll, I think the last ones were made in the 1950's, really don't get why metric, if all else don't work out I can always get a machine shop to cut it down to 1 1/2" X 8 threads that way I can switch from it to the Atlas, Logan lathe, my thinking which could be wrong., thanks for the help fellows, Joe

 

[william_b_noble]

I have some Delrin, going to try and cut some threads before I do the internal one but if worse comes to worse, I will take the dividing head apart and have a real machinist cut me some 1 1/2 X 8 T.P.I. that was I can if have to ever switch from Lathe to dividing head or the other way, I did measure and it is 4 T.P.I. Metric.

I buy nuts in the standard sizes,not sure I have 1 3/4 by 8. A tap from ebay is also cheap, why are you messing with metric threads?

 

[phred]

It's probably a 4mm pitch M39 as used on some ( like mine ) Hare & Forbes supplied lathe.
although the supplied docs do not show it, it is possible to cut the 4mm pitch thread as I have made several backplates for different chucks.