Arfa Daily wrote:

Thanks for that John. So, 1/2" and 3/4". Where on earth is that measured to
equate to the sizes I measured at the threads ? The logic and history of
plumbing fitting sizes are beyond me ... :-)

The 1/2" is the inside diameter of the an iron barrel pipe. When you
thread the outside you end up with something just over 0.8" because of
the thick pipe wall.

--
Cheers,

John.

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