TheOldHokie
Well-known member
Lifetime Member
Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
National pipe thread has a flank angle of 60 degrees. British pipe thread is 55 degrees. Plus the major diameters are different. I would strongly recommend using the proper tap.I might be out in left field on this but isn't 3/4 npt 3/4-14? If it is and the same od would you be able to chase the thread carefully with a pipe tap? the taper might actually make it easier to start straight. I am working from memory here and was thinking 3/4 pipe is about an inch and an eight od.
Bill
Dan