On Tue, 04 Aug 2009 23:38:38 -0500, Tim Wescott
wrote:

There was a thread here about a month ago about restoring an Italian
espresso machine that had metric diameter parts with 'merican thread
pitches.

So I was visiting my sister, and my nephew asks if I can make him a part
for an accordion and hands we a little bent piece of wire that -- shoot
me if I'm wrong -- is threaded with 3mm x 40TPI at the ends.

Cool.

I started talking about this and my sister accused me of not really
belonging in the family seeing as how I'm one of those _restorer_ freaks,
and not the least bit a hot rodder.

So of course then I had to start talking about getting just the right
alloy of 3mm brass stock, and finding a plater, and about how maybe it
would be a crime to fix the damn thing AT ALL because that would mess up
it's provenance.

Fun fun. (the part is made, with 1/8" drill rod and 4-40 threads).

are the threads 55degree angle or 60 degree angle?

eighth inch whitworth is 40 tpi