Threadmill

OK Guys,
I have uploaded a file to the files section called Threadmill.jpg
This shows One holder in a collet chuck and a second tool on the
right.
The brass test piece is in the middle and is about 2" diameter. This
thread of 8TPI was cut in one pass and one revolution. As an idea of
scale the holder on the left has a 3/4" shank.
I also use this tool to screwcut internal threads on the lathe.
John Stevenson