Large old Columbian vise disassembly and inspection

Found a old vise in an antique mall and I think it might be somewhat unique

[tmwest]

I have a 604-2 same Vise it was my grandfathers.

[joeyshook]

i have a 504 1/2 and im halfway through stripping it and cleaning, polishing etc. and there is a steel ring around the long screw in the bottom, it seems to be held on by a set screw, but it marred up and i cant get it out to save my life. do you have any idea what i should do to remove and hopefully not destroy the original set screw? I got this thing for free and i would not like to have to put money into it ha ha .

[nathanbottjer]

Clean up the bottom there should be numbers on the bottom. Use a flap disc but becareful when doing it. It looks kinda like my number 604

[adamsicilia]

I'm pretty sure that's the columbian 604 vise I just got the same one from a great uncle. I'm pretty sure its pre ww2.

[gatsbylight]

I have one of those. It looks my 604. *Here's a question:* Does anyone happen to know if the lockscrew (the small handle that you tighten for the swivel basel) on these vises is a standard bolt size. The bolt thread diameter measures a true 1/2", but the pitch doesn't seem like a standard 13 TPI... it looks like 12 threads per inch.