I didn't see the original post on this subject, however for 35mm cameras,
and at least some of the old (120) folding cameras, it has been 1/4 inch
Whitworth for decades.

There was / is a larger size in use - of a broader diameter, for use with
heavier gear (medium and large format).

(been a photog. since late 1970s)

Hope that helps.

Keith




"Chris Hodges" wrote in message
k...
Dave Plowman (News) wrote:
In article ,
Chris Hodges wrote:

I'm trying to find out whether the ¼" bush for a camera tripod is a
Whitworth or a UNC thread - both are 20 tpi, but of course the thread
form is different.
Any ideas please?


It's Whitworth. Dates back to before Unified.



But UNC works for most jobs and is much easier to get hold of.


I'm not so sure. Near everything is metric these days. And UNC was never
as common as UNF on cars.


The yanks use 1/4"-20 quit a bit and it's used on optical kit - very easy
to get hold of for me. RS do boxes of UNC screws, but only studs in BSW.

Chris

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