Sounds like they had either the "new guy" or the apprentice do it,
and he ran the NPT tap right through the plate or maifold or what-ever
it is, as he would with a standard tap. Maybe they can take it out to
3/4" and use a 3/4 to 1/2 breducing bushing (standfdard stuff
anywhere).

Take care.

Brian Lawson,
Bothwell, Ontario.

XXXXXXXXXXXXXXXXXXXXXXXXX
On 7 Feb 2005 06:50:09 -0800, wrote:

I need a bit of advice. I just had a job completed by a machine shop
that called for a 1/2" NTP and 1/4" NPT hole. The part was titled
"manifold". The parts just arrived with the 1/2" NPT hole tapped to the
bottom of a 1 1/8" deep port (will never seal)and a correctly tapped
1/4" NPT hole. The machine shop says it was my fault because I didn't
specify the thread length and I will now have to pay for a "rush run"
if I need to meet my deadline. Isn't NPT supposed to be tapped within a
certain range? Shouldn't they have asked if there was any doubt? I
think that they should have asked. Am I wrong?

Thanks,

RR