South Bend 34-C Spindle thread identification assistance

[EW57]

Greetings, I'm the caretaker of what I believe is a pre 1920 South Bend 34-C & I'd like to affix a different chuck. Before I remove this chuck, I was hoping to learn more about what thread size & pitch the 34C originally came with, but I'm having some difficulty finding info on models this old.

Any info or assistance would be greatly appreciated.

 

[DavidR8]

You might just have to pull the chuck and see how it measures out...

 

[Superburban]

I agree, take it off to be sure.

Digging through all the stuff I have, all I can find is 1&3/4". No thread count given.

 

[EW57]

Thanks the the replies, I pulled the chuck today & it appears to be a 1.75x8.