In article ,
"DazFNQ" wrote:

Ha It gets better, in the Hare & Forbes brochure it says theat the leadscrew
is metric, but another source of information for the same lathe says that it
is an imperial leadscrew.

Have discovered that its pitch is 3mm and it has 8tpi (butress thread)

Can't be both. 8 tpi is (1/8)(25.4)= 3.175 mm pitch, not 3.000 mm pitch.

It's close enough that a thread pitch gage may have difficulty
distinguishing unless one takes the leadscrew off the lathe.

A better way to measure in place is with a dial indicator stuck to the
bed indicating horizontal travel of the carriage with half-nut engaged
while manually turning the leadscrew and counting turns.

Joe Gwinn