Dave Plowman (News) wrote:

Some of the smaller makers may well have continued to use the pre-war
threads until much later. Rolls Royce certainly did for some things.

Were they the manufacturers that introduce the 12 point nuts and bolts?

They were still being used ten years ago on their aero engines.

Although most of the UK motor industry did adopt the unified threads I'm
not so sure this applied to the US. People there still talk about AC and
AF.

That has prompted me to get my old apprentice books out to check :-)


Dave