The Stovebolt Site Forums The Shop Area Driveline Brake junction block, 1/2 ton?

I've thrown this out on several occasions, but since were're on
the subject of brass fittings I'll try again, never know who
when a whiz bang machinist might have joined up yesterday.
Over the past decade or so I've been trying to figure out how to
machine a female SAS J512 inverted flare seat in a brass block
using a manual Bridgeport milling machine.
Mill cutters are avalable to cut the basic shape, but the real
trick comes in with the female thread. The thread realy has to
go just about to the bottom of the bore. You say bottom tap?
Well yes, a bottom tap is necessary but the problem is the 45°
cone in the bottom that your special cutter formed. It appears
that the center of the tap would need to be V'ed out to clear
the cone. This would not be a problem with a CNC machine, there
you could program it to single point a thread right to the
bottom of the bore, but most of us don't have access to one of
those.
So, I can have a cutter ground to give me the shape I need but
HOW IN THE WORLD CAN I CUT A THREAD IN THE TAP DRILLED HOLE??????

Denny G
Sandwich, IL