I just bought a self bleeding valve to fit into a half inch thread. What arrived was 3/4". It's sold as 1/2" BSP, and according to this page, 1/2" BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

On 3/14/2017 5:48 PM, James Wilkinson Sword wrote:
I just bought a self bleeding valve to fit into a half inch thread.
What arrived was 3/4". It's sold as 1/2" BSP, and according to this
page, 1/2" BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It is pretty straightforward

http://www.bspt.co.uk/

On Tue, 14 Mar 2017 17:52:00 -0000, newshound wrote:

On 3/14/2017 5:48 PM, James Wilkinson Sword wrote:
I just bought a self bleeding valve to fit into a half inch thread.
What arrived was 3/4". It's sold as 1/2" BSP, and according to this
page, 1/2" BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It is pretty straightforward

http://www.bspt.co.uk/

That makes absolutely no sense at all.

From your link: "The size was originally based on the inner diameter measured in inches of a steel tube for which the thread was intended."

I've bought something stating it's a 1/2" BSP, yet the outer diameter of its male thread is 3/4", 50% bigger. How can the device I purchased be intended to fit into a steel tube of an internal diameter 2/3rds of the width of the device?

Where is this 1/2" measurement taken in relation to my device?

--
"Click cancel to discontinue starting" - Mac OS 9

On 14-Mar-17 6:01 PM, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 17:52:00 -0000, newshound
wrote:

On 3/14/2017 5:48 PM, James Wilkinson Sword wrote:
I just bought a self bleeding valve to fit into a half inch thread.
What arrived was 3/4". It's sold as 1/2" BSP, and according to this
page, 1/2" BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It is pretty straightforward

http://www.bspt.co.uk/

That makes absolutely no sense at all.

From your link: "The size was originally based on the inner diameter
measured in inches of a steel tube for which the thread was intended."

More correctly, for sizes under 3", it was originally wrought iron pipe
(not tube) and for 3" and above, cast iron pipe. Steel pipe came later.

I've bought something stating it's a 1/2" BSP, yet the outer diameter of
its male thread is 3/4", 50% bigger.

It should be 0.825" OD.

How can the device I purchased be
intended to fit into a steel tube of an internal diameter 2/3rds of the
width of the device?

It is really quite simple. For water flow, it is the bore that is
important, so Imperial pipes are designated by that. You then need to
add the thickness of the walls to find the diameter of the thread that
can be cut onto that pipe. In the days of Imperial measure, things were
not done to suit the lowest common denominator.

Where is this 1/2" measurement taken in relation to my device?

If you measured a BSP thread that was approximately 1/2" OD, then that
is 1/4" BSP. You only need to look up a BSP thread table to find this out.



--
--

Colin Bignell

On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

On 14-Mar-17 6:01 PM, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 17:52:00 -0000, newshound
wrote:

On 3/14/2017 5:48 PM, James Wilkinson Sword wrote:
I just bought a self bleeding valve to fit into a half inch thread.
What arrived was 3/4". It's sold as 1/2" BSP, and according to this
page, 1/2" BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It is pretty straightforward

http://www.bspt.co.uk/

That makes absolutely no sense at all.

From your link: "The size was originally based on the inner diameter
measured in inches of a steel tube for which the thread was intended."

More correctly, for sizes under 3", it was originally wrought iron pipe
(not tube) and for 3" and above, cast iron pipe. Steel pipe came later.

I've bought something stating it's a 1/2" BSP, yet the outer diameter of
its male thread is 3/4", 50% bigger.

It should be 0.825" OD.

Probably, I measured it with callipers and it was just over 3/4". I wasn't being exact, just annoyed it wasn't anything like the 1/2" I was expecting.

I was told they're standard, yet I can see three different sizes on the radiators in my house alone, with most of the radiators having a different size on each end!

How can the device I purchased be
intended to fit into a steel tube of an internal diameter 2/3rds of the
width of the device?

It is really quite simple. For water flow, it is the bore that is
important, so Imperial pipes are designated by that. You then need to
add the thickness of the walls to find the diameter of the thread that
can be cut onto that pipe. In the days of Imperial measure, things were
not done to suit the lowest common denominator.

So the pipe wall was so thick that the inner diameter was 0.5" and the outer 0.825"? I could understand that with HEP pipe, but not metal.

Where is this 1/2" measurement taken in relation to my device?

If you measured a BSP thread that was approximately 1/2" OD, then that
is 1/4" BSP. You only need to look up a BSP thread table to find this out.

I cannot find a 1/4" self bleeding valve (only 1/8 and 1/2), but I did find a 1/4 BSP to 1/2 BSP adapter, so I'll try that when it arrives.

James Wilkinson Sword wrote:
I just bought a self bleeding valve to fit into a half inch thread. What
arrived was 3/4". It's sold as 1/2" BSP, and according to this
page, 1/2" BSP is meant to be 3/4". WTF?
https://en.wikipedia.org/wiki/Britis...e_thread_sizes

If for a radiator, then you have a leak somewhere.
Fix the leak.

On 14/03/17 18:33, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

So the pipe wall was so thick that the inner diameter was 0.5" and the
outer 0.825"? I could understand that with HEP pipe, but not metal.

Iron pipe is pretty thick walled.

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

On 14-Mar-17 6:01 PM, James Wilkinson Sword wrote:
snip

Where is this 1/2" measurement taken in relation to my device?

If you measured a BSP thread that was approximately 1/2" OD, then that
is 1/4" BSP. You only need to look up a BSP thread table to find this out.

I cannot find a 1/4" self bleeding valve (only 1/8 and 1/2), but I did
find a 1/4 BSP to 1/2 BSP adapter, so I'll try that when it arrives.

Perhaps you need to measure the internal diameter of your female thread
a bit more carefully than "about 1/2" because it might well be 1/8"
BSP. The manual one on my boiler is, FWIW. Though the automatic one on
the same boiler is 1/4" (or possibly 3/8", I haven't removed it) BSP so
perhaps that is what you want.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!


--

Roger Hayter

On Tue, 14 Mar 2017 19:58:18 -0000, Tim Watts wrote:

On 14/03/17 18:33, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

So the pipe wall was so thick that the inner diameter was 0.5" and the
outer 0.825"? I could understand that with HEP pipe, but not metal.

Iron pipe is pretty thick walled.

To allow for rust?

--
It is impossible to hold a sandwich between your elbows and eat it.

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

On 14-Mar-17 6:01 PM, James Wilkinson Sword wrote:
snip

Where is this 1/2" measurement taken in relation to my device?

If you measured a BSP thread that was approximately 1/2" OD, then that
is 1/4" BSP. You only need to look up a BSP thread table to find this out.

I cannot find a 1/4" self bleeding valve (only 1/8 and 1/2), but I did
find a 1/4 BSP to 1/2 BSP adapter, so I'll try that when it arrives.

Perhaps you need to measure the internal diameter of your female thread
a bit more carefully than "about 1/2" because it might well be 1/8"
BSP. The manual one on my boiler is, FWIW. Though the automatic one on
the same boiler is 1/4" (or possibly 3/8", I haven't removed it) BSP so
perhaps that is what you want.

The calipers said 14mm, reading the outer diameter of the thread of what used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down boxes.

--
Archimedes principle: When a body is fully immersed in water, the telephone rings.

On Tuesday, 14 March 2017 20:37:59 UTC, James Wilkinson Sword wrote:
It is impossible to hold a sandwich between your elbows and eat it.

But if you have a filled baguette you can do a good job of tongueing out the filling :-)

Owain

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread of what
used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down boxes.

Should all work then! Copious PTFE tape should work for the taper one,
the other may need tape, fibre washer *and* sealant if both threads are
parallel.

--

Roger Hayter

On Tuesday, 14 March 2017 20:37:59 UTC, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 19:58:18 -0000, Tim Watts wrote:

On 14/03/17 18:33, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

So the pipe wall was so thick that the inner diameter was 0.5" and the
outer 0.825"? I could understand that with HEP pipe, but not metal.

Iron pipe is pretty thick walled.

To allow for rust?


No, to allow for the threads to be cut into it.
There are three steel pipe wall thicknesses commonly available for different pressures.

http://www.engineeringtoolbox.com/bs...ions-d_97.html

The outside for all gauges is constant.
The bore varies depending on the pressure the pipe is rated for.
This is so all pipes take the same BSP thread when they are threaded.

Hence the bore size quoted is "nominal".

On Tuesday, 14 March 2017 18:33:46 UTC, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

On 14-Mar-17 6:01 PM, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 17:52:00 -0000, newshound
wrote:

On 3/14/2017 5:48 PM, James Wilkinson Sword wrote:
I just bought a self bleeding valve to fit into a half inch thread.
What arrived was 3/4". It's sold as 1/2" BSP, and according to this
page, 1/2" BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It is pretty straightforward

http://www.bspt.co.uk/

That makes absolutely no sense at all.

From your link: "The size was originally based on the inner diameter
measured in inches of a steel tube for which the thread was intended."

More correctly, for sizes under 3", it was originally wrought iron pipe
(not tube) and for 3" and above, cast iron pipe. Steel pipe came later.

I've bought something stating it's a 1/2" BSP, yet the outer diameter of
its male thread is 3/4", 50% bigger.

It should be 0.825" OD.

Probably, I measured it with callipers and it was just over 3/4". I wasn't being exact, just annoyed it wasn't anything like the 1/2" I was expecting.

I was told they're standard, yet I can see three different sizes on the radiators in my house alone, with most of the radiators having a different size on each end!

How can the device I purchased be
intended to fit into a steel tube of an internal diameter 2/3rds of the
width of the device?

It is really quite simple. For water flow, it is the bore that is
important, so Imperial pipes are designated by that. You then need to
add the thickness of the walls to find the diameter of the thread that
can be cut onto that pipe. In the days of Imperial measure, things were
not done to suit the lowest common denominator.

So the pipe wall was so thick that the inner diameter was 0.5" and the outer 0.825"? I could understand that with HEP pipe, but not metal.

Where is this 1/2" measurement taken in relation to my device?

If you measured a BSP thread that was approximately 1/2" OD, then that
is 1/4" BSP. You only need to look up a BSP thread table to find this out.

I cannot find a 1/4" self bleeding valve (only 1/8 and 1/2), but I did find a 1/4 BSP to 1/2 BSP adapter, so I'll try that when it arrives.

What you want is one of these.
https://www.amazon.co.uk/s/?ie=UTF8&...l_559by5hqwq_b

(Top picture).

"James Wilkinson Sword" wrote in message news

I just bought a self bleeding valve to fit into a half inch thread. What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page, 1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Andrew

On Wed, 15 Mar 2017 01:18:10 -0000, Roger Hayter wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread of what
used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down boxes.

Should all work then! Copious PTFE tape should work for the taper one,
the other may need tape, fibre washer *and* sealant if both threads are
parallel.

I know about PTFE tape, but there is something else I can do if the male is 14mm and the female is 15mm?

--
A Jesus of mass J travelling at a speed of 27 meters/second collides with a stationary Moses of mass M.
Assuming any elastic deformation is lossless and perfectly reversible, calculate how long it will be until the next Passover.

On Wed, 15 Mar 2017 07:37:59 -0000, harry wrote:

On Tuesday, 14 March 2017 20:37:59 UTC, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 19:58:18 -0000, Tim Watts wrote:

On 14/03/17 18:33, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

So the pipe wall was so thick that the inner diameter was 0.5" and the
outer 0.825"? I could understand that with HEP pipe, but not metal.

Iron pipe is pretty thick walled.

To allow for rust?


No, to allow for the threads to be cut into it.
There are three steel pipe wall thicknesses commonly available for different pressures.

http://www.engineeringtoolbox.com/bs...ions-d_97.html

The outside for all gauges is constant.
The bore varies depending on the pressure the pipe is rated for.
This is so all pipes take the same BSP thread when they are threaded.

Hence the bore size quoted is "nominal".

Make the whole length of pipe thicker just to add a thread on the end?

--
Why is there no Disneyland China?
No one's tall enough to go on the good rides.

On Wed, 15 Mar 2017 07:42:02 -0000, harry wrote:

On Tuesday, 14 March 2017 18:33:46 UTC, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar wrote:

On 14-Mar-17 6:01 PM, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 17:52:00 -0000, newshound
wrote:

On 3/14/2017 5:48 PM, James Wilkinson Sword wrote:
I just bought a self bleeding valve to fit into a half inch thread.
What arrived was 3/4". It's sold as 1/2" BSP, and according to this
page, 1/2" BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It is pretty straightforward

http://www.bspt.co.uk/

That makes absolutely no sense at all.

From your link: "The size was originally based on the inner diameter
measured in inches of a steel tube for which the thread was intended."

More correctly, for sizes under 3", it was originally wrought iron pipe
(not tube) and for 3" and above, cast iron pipe. Steel pipe came later.

I've bought something stating it's a 1/2" BSP, yet the outer diameter of
its male thread is 3/4", 50% bigger.

It should be 0.825" OD.

Probably, I measured it with callipers and it was just over 3/4". I wasn't being exact, just annoyed it wasn't anything like the 1/2" I was expecting.

I was told they're standard, yet I can see three different sizes on the radiators in my house alone, with most of the radiators having a different size on each end!

How can the device I purchased be
intended to fit into a steel tube of an internal diameter 2/3rds of the
width of the device?

It is really quite simple. For water flow, it is the bore that is
important, so Imperial pipes are designated by that. You then need to
add the thickness of the walls to find the diameter of the thread that
can be cut onto that pipe. In the days of Imperial measure, things were
not done to suit the lowest common denominator.

So the pipe wall was so thick that the inner diameter was 0.5" and the outer 0.825"? I could understand that with HEP pipe, but not metal.

Where is this 1/2" measurement taken in relation to my device?

If you measured a BSP thread that was approximately 1/2" OD, then that
is 1/4" BSP. You only need to look up a BSP thread table to find this out.

I cannot find a 1/4" self bleeding valve (only 1/8 and 1/2), but I did find a 1/4 BSP to 1/2 BSP adapter, so I'll try that when it arrives.

What you want is one of these.
https://www.amazon.co.uk/s/?ie=UTF8&...l_559by5hqwq_b

(Top picture).

Yes, I've now bought something like that from Ebay.

--
Why is there no Disneyland China?
No one's tall enough to go on the good rides.

On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson wrote:

"James Wilkinson Sword" wrote in message news

I just bought a self bleeding valve to fit into a half inch thread. What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page, 1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you can easily divide by ten to get the next size. A 15mm pipe that actually measures 15mm.


--
I couldn't repair your brakes, so I made your horn louder.

In article , James Wilkinson Sword
wrote:
On Wed, 15 Mar 2017 01:18:10 -0000, Roger Hayter wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter
wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread of
what used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down
boxes.

Should all work then! Copious PTFE tape should work for the taper one,
the other may need tape, fibre washer *and* sealant if both threads are
parallel.

I know about PTFE tape, but there is something else I can do if the male
is 14mm and the female is 15mm?

hemp and putty used to the used.

--
from KT24 in Surrey, England

On 3/15/2017 1:15 PM, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news

I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come
to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can easily divide by ten to get the next size. A 15mm pipe that
actually measures 15mm.


Predictably, I am with Andrew.

Standardisation, of course, started in the UK in the days when the world
was a very much less connected place.

I'm just waiting for the Brexiters to say we should ditch all this
Froggy metric stuff and get back to proper Imperial units (like they
still use in Trumpland).

On 15/03/17 13:03, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 01:18:10 -0000, Roger Hayter wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter
wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread of what
used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down
boxes.

Should all work then! Copious PTFE tape should work for the taper one,
the other may need tape, fibre washer *and* sealant if both threads are
parallel.

I know about PTFE tape, but there is something else I can do if the male
is 14mm and the female is 15mm?


I made my son do a PTFE tape joing on a pressure washer part the other
day Little wibbler will thank me one day!

newshound wrote:
On 3/15/2017 1:15 PM, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've
swept up
and stored over my considerable years from childhood have never come
to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things,
schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can easily divide by ten to get the next size. A 15mm pipe that
actually measures 15mm.


Predictably, I am with Andrew.

Standardisation, of course, started in the UK in the days when the world
was a very much less connected place.

I'm just waiting for the Brexiters to say we should ditch all this
Froggy metric stuff and get back to proper Imperial units (like they
still use in Trumpland).

You mean the imperial people with 2L bottles of coke?

"James Wilkinson Sword" wrote in message news

On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news

I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come to
the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you can
easily divide by ten to get the next size. A 15mm pipe that actually
measures 15mm.



Ah - is that the measurement system based on an incorrect calculation for
the circumference of the Earth, imposed on (initially) France by a one armed
Corsican in a silly hat

-- yes I use that system almost exclusively in my workshop, but am also able
to work in other measurement systems with equal facility !

Andrew

On Wed, 15 Mar 2017 15:46:09 -0000, Andrew Mawson wrote:

"James Wilkinson Sword" wrote in message news

On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come to
the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you can
easily divide by ten to get the next size. A 15mm pipe that actually
measures 15mm.



Ah - is that the measurement system based on an incorrect calculation for
the circumference of the Earth, imposed on (initially) France by a one armed
Corsican in a silly hat

-- yes I use that system almost exclusively in my workshop, but am also able
to work in other measurement systems with equal facility !

Easier in multiples of 10.

--
Confucius say: "Foolish man give wife grand piano. Wise man give wife upright organ."

On Wed, 15 Mar 2017 13:45:37 -0000, newshound wrote:

On 3/15/2017 1:15 PM, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come
to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can easily divide by ten to get the next size. A 15mm pipe that
actually measures 15mm.


Predictably, I am with Andrew.

Standardisation, of course, started in the UK in the days when the world
was a very much less connected place.

I'm just waiting for the Brexiters to say we should ditch all this
Froggy metric stuff and get back to proper Imperial units (like they
still use in Trumpland).

I like metric, but I don't se why we should accept every law the frogs come up with.

--
Your mouse has moved. Windows must be restarted for this change to take effect.

On Wed, 15 Mar 2017 14:14:10 -0000, Capitol wrote:

newshound wrote:
On 3/15/2017 1:15 PM, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've
swept up
and stored over my considerable years from childhood have never come
to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things,
schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can easily divide by ten to get the next size. A 15mm pipe that
actually measures 15mm.


Predictably, I am with Andrew.

Standardisation, of course, started in the UK in the days when the world
was a very much less connected place.

I'm just waiting for the Brexiters to say we should ditch all this
Froggy metric stuff and get back to proper Imperial units (like they
still use in Trumpland).

You mean the imperial people with 2L bottles of coke?

Oh wow, you found one example and think that proves him wrong.

--
Balderdash (n.), a rapidly receding hairline.

On Wed, 15 Mar 2017 13:21:22 -0000, charles wrote:

In article , James Wilkinson Sword
wrote:
On Wed, 15 Mar 2017 01:18:10 -0000, Roger Hayter wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter
wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread of
what used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down
boxes.

Should all work then! Copious PTFE tape should work for the taper one,
the other may need tape, fibre washer *and* sealant if both threads are
parallel.

I know about PTFE tape, but there is something else I can do if the male
is 14mm and the female is 15mm?

hemp and putty used to the used.

Is I used to using it in a used state? Or what is you thinking?

--
Black.... like the clouds of death that follow me into the forest of doom and hide in the wardrobe of darkness! Blaaaackk!

James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 07:37:59 -0000, harry
wrote:

On Tuesday, 14 March 2017 20:37:59 UTC, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 19:58:18 -0000, Tim Watts
wrote:

On 14/03/17 18:33, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar
wrote:

So the pipe wall was so thick that the inner diameter was 0.5" and
the
outer 0.825"? I could understand that with HEP pipe, but not metal.

Iron pipe is pretty thick walled.

To allow for rust?


No, to allow for the threads to be cut into it.
There are three steel pipe wall thicknesses commonly available for
different pressures.

http://www.engineeringtoolbox.com/bs...ions-d_97.html

The outside for all gauges is constant.
The bore varies depending on the pressure the pipe is rated for.
This is so all pipes take the same BSP thread when they are threaded.

Hence the bore size quoted is "nominal".

Make the whole length of pipe thicker just to add a thread on the end?

Or the middle, or where ever you cut it.

"James Wilkinson Sword" wrote in message news

On Wed, 15 Mar 2017 15:46:09 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news

On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept
up
and stored over my considerable years from childhood have never come to
the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things,
schools
had workshops with real machines, and we made real objects. Nowadays
its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can
easily divide by ten to get the next size. A 15mm pipe that actually
measures 15mm.



Ah - is that the measurement system based on an incorrect calculation for
the circumference of the Earth, imposed on (initially) France by a one
armed
Corsican in a silly hat

-- yes I use that system almost exclusively in my workshop, but am also
able
to work in other measurement systems with equal facility !

Easier in multiples of 10.


James, you will be absolutely delighted to know that the "ISO" metric pipe
threads (GXX ) are entirely based on British Standard Pipe threads so you
had better get used to it

Andrew

On Wednesday, 15 March 2017 13:03:46 UTC, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 01:18:10 -0000, Roger Hayter wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread of what
used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down boxes.

Should all work then! Copious PTFE tape should work for the taper one,
the other may need tape, fibre washer *and* sealant if both threads are
parallel.

I know about PTFE tape, but there is something else I can do if the male is 14mm and the female is 15mm?


Pipe threads are taper cut,
Sealant on the thread is squeezed out as the pipe is screed into the fitting.

Larger pipes are cut with adjustable dies so whatever thread size deemed appropiate can be cut.

Traditionally "Boss White" and hemp was used with water/steam.
And"Stag" with petrol/oil.

On Wed, 15 Mar 2017 13:45:37 +0000, newshound
wrote:


I'm just waiting for the Brexiters to say we should ditch all this
Froggy metric stuff and get back to proper Imperial units (like they
still use in Trumpland).

Isn't there a case for the them being called Imperial because they
originated in Imperial Rome rather than the days of the British
Empire.

G.Harman

On Wednesday, 15 March 2017 11:54:47 UTC, Andrew Mawson wrote:
"James Wilkinson Sword" wrote in message news

I just bought a self bleeding valve to fit into a half inch thread. What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page, 1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!


True.

On Wednesday, 15 March 2017 13:45:44 UTC, newshound wrote:
On 3/15/2017 1:15 PM, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come
to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can easily divide by ten to get the next size. A 15mm pipe that
actually measures 15mm.


Predictably, I am with Andrew.

Standardisation, of course, started in the UK in the days when the world
was a very much less connected place.

I'm just waiting for the Brexiters to say we should ditch all this
Froggy metric stuff and get back to proper Imperial units (like they
still use in Trumpland).

BSP pipe threads are universal.

On Wednesday, 15 March 2017 16:04:29 UTC, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 15:46:09 -0000, Andrew Mawson wrote:

"James Wilkinson Sword" wrote in message news

On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come to
the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you can
easily divide by ten to get the next size. A 15mm pipe that actually
measures 15mm.



Ah - is that the measurement system based on an incorrect calculation for
the circumference of the Earth, imposed on (initially) France by a one armed
Corsican in a silly hat

-- yes I use that system almost exclusively in my workshop, but am also able
to work in other measurement systems with equal facility !

Easier in multiples of 10.

Easier to make a mistake too.

harry wrote:
On Wednesday, 15 March 2017 13:03:46 UTC, James Wilkinson Sword
wrote:
On Wed, 15 Mar 2017 01:18:10 -0000, Roger Hayter
wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter
wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread
of what used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing
is commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop
down boxes.

Should all work then! Copious PTFE tape should work for the taper
one, the other may need tape, fibre washer *and* sealant if both
threads are parallel.

I know about PTFE tape, but there is something else I can do if the
male is 14mm and the female is 15mm?


Pipe threads are taper cut,
Sealant on the thread is squeezed out as the pipe is screed into the
fitting.

Larger pipes are cut with adjustable dies so whatever thread size
deemed appropiate can be cut.

Traditionally "Boss White" and hemp was used with water/steam.
And"Stag" with petrol/oil.

In a very past life I've used Boss White and hemp with water. The plumber
who trained me was very old school. He must now be very dead.
I've also, out of desperation used Stag on water joints. It worked but made
a right mess.

"harry" wrote in message
...

On Wednesday, 15 March 2017 13:03:46 UTC, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 01:18:10 -0000, Roger Hayter
wrote:

James Wilkinson Sword wrote:

On Tue, 14 Mar 2017 20:10:11 -0000, Roger Hayter
wrote:
snip

The calipers said 14mm, reading the outer diameter of the thread of
what
used to be in it.

BTW, your adapter is M to F increasing, is it? M to F reducing is
commoner and won't help you!

Yes, I selected the female and male sizes seperately from drop down
boxes.

Should all work then! Copious PTFE tape should work for the taper one,
the other may need tape, fibre washer *and* sealant if both threads are
parallel.

I know about PTFE tape, but there is something else I can do if the male
is 14mm and the female is 15mm?


Pipe threads are taper cut,
Sealant on the thread is squeezed out as the pipe is screed into the
fitting.

Larger pipes are cut with adjustable dies so whatever thread size deemed
appropiate can be cut.

Traditionally "Boss White" and hemp was used with water/steam.
And"Stag" with petrol/oil.


Not quite correct. Pipe threads can be BSPP (BS pipe parallel) or BSPT (BS
pipe taper)

BSPT theoretically seals with no gunge added, but it's a brave man that
doesn't give it a smear of Bosswhite, if only as a lubricant. Nowadays I
only use PTFE tape for temporary test set ups. Fr permanent screwed pipe
assemblies I now use one of the Loctite pipe sealants - 545 for small stuff
and 577 over 3/4" BSP

Andrew

On Wed, 15 Mar 2017 16:33:31 -0000, F Murtz wrote:

James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 07:37:59 -0000, harry
wrote:

On Tuesday, 14 March 2017 20:37:59 UTC, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 19:58:18 -0000, Tim Watts
wrote:

On 14/03/17 18:33, James Wilkinson Sword wrote:
On Tue, 14 Mar 2017 18:24:38 -0000, Nightjar
wrote:

So the pipe wall was so thick that the inner diameter was 0.5" and
the
outer 0.825"? I could understand that with HEP pipe, but not metal.

Iron pipe is pretty thick walled.

To allow for rust?


No, to allow for the threads to be cut into it.
There are three steel pipe wall thicknesses commonly available for
different pressures.

http://www.engineeringtoolbox.com/bs...ions-d_97.html

The outside for all gauges is constant.
The bore varies depending on the pressure the pipe is rated for.
This is so all pipes take the same BSP thread when they are threaded.

Hence the bore size quoted is "nominal".

Make the whole length of pipe thicker just to add a thread on the end?

Or the middle, or where ever you cut it.

So we didn't use to have compression fittings, solder, etc? Creating a thread on something sounds like a lot of hard work. And you've wasted huge amounts of material making the pipe thicker all the way along.

--
A single blonde pregnant girl goes to the grocery store. A couple that she knows notices she's pregnant.
The lady asks her, "Whose baby is it?"
The blonde says, "Well, I don't know they are going to do blood tests, but I think it's mine."

On Wed, 15 Mar 2017 16:39:13 -0000, Andrew Mawson wrote:

"James Wilkinson Sword" wrote in message news

On Wed, 15 Mar 2017 15:46:09 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept
up
and stored over my considerable years from childhood have never come to
the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things,
schools
had workshops with real machines, and we made real objects. Nowadays
its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can
easily divide by ten to get the next size. A 15mm pipe that actually
measures 15mm.



Ah - is that the measurement system based on an incorrect calculation for
the circumference of the Earth, imposed on (initially) France by a one
armed
Corsican in a silly hat

-- yes I use that system almost exclusively in my workshop, but am also
able
to work in other measurement systems with equal facility !

Easier in multiples of 10.


James, you will be absolutely delighted to know that the "ISO" metric pipe
threads (GXX ) are entirely based on British Standard Pipe threads so you
had better get used to it

Link?

--
Recent medical journals are now advising doctors that, should they discover a patient has an AOL account, they should refrain from telling the patient they have sugar in their urine.
Studies show these people go home and **** on their cornflakes.

On Wed, 15 Mar 2017 16:45:10 -0000, harry wrote:

On Wednesday, 15 March 2017 13:45:44 UTC, newshound wrote:
On 3/15/2017 1:15 PM, James Wilkinson Sword wrote:
On Wed, 15 Mar 2017 11:55:07 -0000, Andrew Mawson
wrote:

"James Wilkinson Sword" wrote in message
news
I just bought a self bleeding valve to fit into a half inch thread.
What
arrived was 3/4". It's sold as 1/2" BSP, and according to this page,
1/2"
BSP is meant to be 3/4". WTF?

https://en.wikipedia.org/wiki/Britis...e_thread_sizes

It never ceases to amaze me that tit bits of knowledge that I've swept up
and stored over my considerable years from childhood have never come
to the
attention of the younger generation. We as kids were playing with BSP
threads, Whitworth and BSF nuts and bolts, and even UNC / UNF and
occasionally BSCy and NPT . But in those days we did real things, schools
had workshops with real machines, and we made real objects. Nowadays its
virtual models and people know virtually nothing apart from how to push
buttons !!!

Nowadays we normally use more sensible measurements. Metric that you
can easily divide by ten to get the next size. A 15mm pipe that
actually measures 15mm.


Predictably, I am with Andrew.

Standardisation, of course, started in the UK in the days when the world
was a very much less connected place.

I'm just waiting for the Brexiters to say we should ditch all this
Froggy metric stuff and get back to proper Imperial units (like they
still use in Trumpland).

BSP pipe threads are universal.

And stupidly illogical.

--
One frigid morning in North Dakota a man turned up at work much the worse for wear.
"I didn't sleep a wink," he told a coworker. "I was up all night trying to keep my wife's begonia covered against the freezing cold."
"I should be so lucky," his coworker replied. "When it's this cold my wife wears so damn many clothes to bed, I can never get anywhere near her begonia."