Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

While I do not have a Weeden #7 to compare with, I do have a Machinery's Handbook for reference. But without even referencing that I can tell you that a #7 is pretty much never encountered in the Unified Thread system, and so the next larger from a 6-32 would be an 8-32 with a major diameter of about .164". I will point out that anything is possible if Weeden decided, for whatever reason, to use a proprietary thread, which was not at all uncommon back in the day. Otherwise it could just be a 6-32 from a badly worn die, or an undersized 8-32 at the limit of tolerance .... or beyond.

What is the maximum diameter you are getting from the male threads?