Hello all.

The recent thread on taps and dies prompted me to look again at my (yet
unused) all metric set (bought from Screwfix some time ago).
To my surprise, I found the following:
One single short length tap, and one die.
They are marked "NPT 1/8 27". Now, I haven't the slightest idea what they
are for.
I'm not entirely surprised, as this set also contains a screwdriver, centre
punch, thread gauge, and five stud extractors (of the l/h spiral variety).
I'm guessing that they are probably used for "cleaning" damaged threads.

But on what fittings?

Answers will be gratefully received.

Sylvain.

"Sylvain VAN DER WALDE" wrote in message
...
Hello all.

The recent thread on taps and dies prompted me to look again at my (yet
unused) all metric set (bought from Screwfix some time ago).
To my surprise, I found the following:
One single short length tap, and one die.
They are marked "NPT 1/8 27". Now, I haven't the slightest idea what they
are for.
I'm not entirely surprised, as this set also contains a screwdriver,
centre punch, thread gauge, and five stud extractors (of the l/h spiral
variety).
I'm guessing that they are probably used for "cleaning" damaged threads.

But on what fittings?

Answers will be gratefully received.

Sylvain.



Have a look at http://www.natool.com/engdata/data06.php
NPT = US National Pipe Thread
1/8 = nominal size of pipe
27 = threads per inch

PeterK

In an earlier contribution to this discussion,
Sylvain VAN DER WALDE wrote:

Hello all.

The recent thread on taps and dies prompted me to look again at my
(yet unused) all metric set (bought from Screwfix some time ago).
To my surprise, I found the following:
One single short length tap, and one die.
They are marked "NPT 1/8 27". Now, I haven't the slightest idea what
they are for.
I'm not entirely surprised, as this set also contains a screwdriver,
centre punch, thread gauge, and five stud extractors (of the l/h
spiral variety). I'm guessing that they are probably used for
"cleaning" damaged threads.
But on what fittings?

Answers will be gratefully received.

Sylvain.


NPT is a pipe thread used in USA - similar to our BSP.

1/8" NPT is roughly the same size as 1/8" BSP (just under 10mm in diameter)
but has 27 threads per inch compared with BSP's 28.

I have a feeling that things like engine oil pressure switches on cars had
used to use NTP threads. I doubt whether they still do - more likely to be
metric, these days.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

"Roger Mills" wrote in message
...
In an earlier contribution to this discussion,
Sylvain VAN DER WALDE wrote:

Hello all.

The recent thread on taps and dies prompted me to look again at my
(yet unused) all metric set (bought from Screwfix some time ago).
To my surprise, I found the following:
One single short length tap, and one die.
They are marked "NPT 1/8 27". Now, I haven't the slightest idea what
they are for.
I'm not entirely surprised, as this set also contains a screwdriver,
centre punch, thread gauge, and five stud extractors (of the l/h
spiral variety). I'm guessing that they are probably used for
"cleaning" damaged threads.
But on what fittings?

Answers will be gratefully received.

Sylvain.


NPT is a pipe thread used in USA - similar to our BSP.

1/8" NPT is roughly the same size as 1/8" BSP (just under 10mm in
diameter) but has 27 threads per inch compared with BSP's 28.

I have a feeling that things like engine oil pressure switches on cars had
used to use NTP threads. I doubt whether they still do - more likely to be
metric, these days.
--
Cheers,
Roger

Thanks for both useful replies.

Sylvain.

______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!