It would be a 3/8 Unc, and the brass nut thing would be called a brass coupling nut. Normally they are sink plated steel in their common form.
I made some easily on the lathe if you have access?
Thanks a lot :-)
Unfortunately I don't think I know anyone with a lathe. Do you think it might be a good idea to order one made to the right size? Or is there places where you can rent the equipment?
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