On Jul 15, 3:09*am, Nicht die Bohne
wrote:
Hello everyone!

I restore vintage espresso machines and right now I have one machine
with really strange threads, which are used on pipe connections. The
machine was manufactured in Italy in the 50s. Here are some examples:

TPI 20 *diameter 14.9mm = 0.5866"
TPI 20 *diameter 19.25mm * * * *= 0.7578"
TPI 16 *diameter 20.25mm * * * *= 0.7972"
TPI 16 *diameter 22.8mm = 0.8976"
TPI 16 *diameter 27.7mm = 1.0905"

Does anyone know what kind of threads it might be?

Many thanks,
Julius

Hand-chased by some guy on a treadle lathe? You don't NEED dies or
taps to cut threads, they do help to make interchangeable parts,
though. If it's got that hand-made, one-off look, it might have been
done that way.

Stan