The message
from "." contains these words:

That's right - deform the pipe. The olive will be pressed into the
pipe, deforming it in a ring all the way round.

What's wrong with that?

1/ it's copper /tube/

2/ if the olive deforms the tube the joint is over tightened and will weep

Well, I've never had a compression joint leak and those I've taken apart
have all had the olive pressed into the tube slightly. If that isn't
deformed I don't know what is.
I'm using "deformed" in the sense of "taken beyond its elastic limit".
You may be using some other meaning.

--
Skipweasel
Pay no attention to that man behind the curtain.

Guy King wrote:
The message
from "." contains these words:

That's right - deform the pipe. The olive will be pressed into the
pipe, deforming it in a ring all the way round.

What's wrong with that?

1/ it's copper /tube/

2/ if the olive deforms the tube the joint is over tightened and
will weep

Well, I've never had a compression joint leak and those I've taken
apart have all had the olive pressed into the tube slightly. If that
isn't deformed I don't know what is.
I'm using "deformed" in the sense of "taken beyond its elastic limit".
You may be using some other meaning.

perhaps deformed was too strong a term for /compressed/ ?

Dave Plowman (News) wrote:
In article ,
EricP wrote:
5. i'd put a couple of wraps of PTFE tape over the olive as i'd been
advised that this can help stop small leaks (was this my downfall?)

This is the reason.

No it's not.

Compression joints are not PTFE territory.

I'm one of those who does use PTFE round the olive. And non of mine leak -
and certainly don't pull apart.

I use it as well but only on old fittings or where there is a problem.
I've NEVER ever had one leak or one come apart.

I saw Tommy Walsh using the same method recently flame suit on ;-)

What I don't get is this recent puritanical aversion to PTFE tape in
this NG. Has someone gone short on PTFE tape manufacturers' shares?

The message
from "." contains these words:

Well, I've never had a compression joint leak and those I've taken
apart have all had the olive pressed into the tube slightly. If that
isn't deformed I don't know what is.
I'm using "deformed" in the sense of "taken beyond its elastic limit".
You may be using some other meaning.

perhaps deformed was too strong a term for /compressed/ ?

No, compressed is something different. To my mind it implies the ability
to spring back, which pipe won't do after an olive has been squashed on
to it.

--
Skipweasel
Pay no attention to that man behind the curtain.

wrote:
Dave Plowman (News) wrote:
In article ,
EricP wrote:
5. i'd put a couple of wraps of PTFE tape over the olive as i'd been
advised that this can help stop small leaks (was this my downfall?)
This is the reason.
No it's not.

Compression joints are not PTFE territory.
I'm one of those who does use PTFE round the olive. And non of mine leak -
and certainly don't pull apart.

I use it as well but only on old fittings or where there is a problem.
I've NEVER ever had one leak or one come apart.

I saw Tommy Walsh using the same method recently flame suit on ;-)

What I don't get is this recent puritanical aversion to PTFE tape in
this NG. Has someone gone short on PTFE tape manufacturers' shares?

PTFE tape works best in a threaded coupling...as a thread filler, Its
less effective in an olive because by and large, its not strong enough.

All olives MUST permanently deform the copper pipe enough to grip it
reliably.

The problem is once you start, its easy to go too far and get to the
limits of the thread to compress the olive. Such a joint has no more
'slack' left in it, and will be unreliable when re-used. Filling it up
with PTFE tape MAY just bulk it out enough to be watertight..but I am
dubious as to the longevity on high pressure systems.

Guy King wrote:
The message
from "." contains these words:


Well, I've never had a compression joint leak and those I've taken
apart have all had the olive pressed into the tube slightly. If that
isn't deformed I don't know what is.
I'm using "deformed" in the sense of "taken beyond its elastic limit".
You may be using some other meaning.


perhaps deformed was too strong a term for /compressed/ ?


No, compressed is something different. To my mind it implies the ability
to spring back, which pipe won't do after an olive has been squashed on
to it.

Compressed is just the opposite of tensed...

c.f. compressive load and tensile load

Ben

Mungo wrote:

I haven't used the new Monsoon 3 bar shower pump yet but its my first
exposure to push fittings and I must admit to being quite impressed

My (lesser powered) shower pump can on occasion squeeze a trickle of
water out of it's push fittings :-(

Guy King wrote:
The message
from "." contains these words:

Well, I've never had a compression joint leak and those I've taken
apart have all had the olive pressed into the tube slightly. If that
isn't deformed I don't know what is.
I'm using "deformed" in the sense of "taken beyond its elastic
limit". You may be using some other meaning.

perhaps deformed was too strong a term for /compressed/ ?

No, compressed is something different. To my mind it implies the
ability to spring back, which pipe won't do after an olive has been
squashed on to it.

why call it a /compression/ joint then ? in your world it would be
called a deformation joint which it isn't, it's a /compression/ joint.
methinks you're splitting hairs, why is anyones guess but if the
copper *tube* /deforms/ the joint is and will be defective.

In article ,
The Natural Philosopher wrote:
The problem is once you start, its easy to go too far and get to the
limits of the thread to compress the olive. Such a joint has no more
'slack' left in it, and will be unreliable when re-used.

On a 1/2" fitting it requires a brutal effort to tighten one to this
extent. And unlikely to happen unless overlong tools are used.

--
*Work like you don't need the money. Love like you've never been hurt.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
. wrote:
why call it a /compression/ joint then ? in your world it would be
called a deformation joint which it isn't, it's a /compression/ joint.
methinks you're splitting hairs, why is anyones guess but if the
copper *tube* /deforms/ the joint is and will be defective.

Not so. I've taken many apart, which after removing the olive, show clear
signs of the pipe being indented under where the olive was. And non of
them leaked. If you've not seen this I'd say you have little experience.

--
*Red meat is not bad for you. Fuzzy green meat is bad for you.

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 09 May 2006 11:28:38 +0100, The Natural Philosopher
wrote:

wrote:
Dave Plowman (News) wrote:
In article ,
EricP wrote:
5. i'd put a couple of wraps of PTFE tape over the olive as i'd been
advised that this can help stop small leaks (was this my downfall?)
This is the reason.
No it's not.

Compression joints are not PTFE territory.
I'm one of those who does use PTFE round the olive. And non of mine leak -
and certainly don't pull apart.

I use it as well but only on old fittings or where there is a problem.
I've NEVER ever had one leak or one come apart.

I saw Tommy Walsh using the same method recently flame suit on ;-)

What I don't get is this recent puritanical aversion to PTFE tape in
this NG. Has someone gone short on PTFE tape manufacturers' shares?

PTFE tape works best in a threaded coupling...as a thread filler, Its
less effective in an olive because by and large, its not strong enough.

All olives MUST permanently deform the copper pipe enough to grip it
reliably.

The problem is once you start, its easy to go too far and get to the
limits of the thread to compress the olive. Such a joint has no more
'slack' left in it, and will be unreliable when re-used. Filling it up
with PTFE tape MAY just bulk it out enough to be watertight..but I am
dubious as to the longevity on high pressure systems.

If you follow the joints development, it would have been used with
hemp amd mate, which is just PTFE's father, if it was intended to have
such capacity. As you say, it was designed as a mechanical joint where
a harder metal was used to deform a softer one to fill calculated
gaps. Any other use is just misuse for convenience sake.

Redeye wrote:
after a rather more eventful weekend than i was hoping for, i'm hoping
somebody can explain this....

i finished plumbing in everything in my new bathroom a couple of weeks
ago. no real problems and all went quite well. so, i was a bit
surprised to be woken at 1am on saturday to the sound of water running
and a hysterical girlfriend. it appears that one of the compression
joints has spontaneously exploded, allowing mains pressure water to go
everywhere. fortunately no real damage done, just a lot of mopping up
to do downstairs.

the bit i don't understand is why this joint went so suddenly. here's
the facts :
You did not tighten it enough
for 15mm pipe if you tighten the nut as much as you can by hand and
then tighten by a further 3/4 of a complete turn
if it should weep you can tighten by another 1/8 turn
Beware of being told that you cannot over tighten compression fittings
thats a guaranteed way of making them leak
PTFE can be used on the threads but never on the olive

Redeye wrote:
after a rather more eventful weekend than i was hoping for, i'm hoping
somebody can explain this....

i finished plumbing in everything in my new bathroom a couple of weeks
ago. no real problems and all went quite well. so, i was a bit
surprised to be woken at 1am on saturday to the sound of water running
and a hysterical girlfriend. it appears that one of the compression
joints has spontaneously exploded, allowing mains pressure water to go
everywhere. fortunately no real damage done, just a lot of mopping up
to do downstairs.

the bit i don't understand is why this joint went so suddenly. here's
the facts :

you are not the only one to have done this
http://www.nrc.gov/reading-rm/doc-co...2/in92015.html
but then
picture of what will happen if you over tighten a compression fitting
http://www.calormarineshop.co.uk/boa...on_fitting.htm

In article . com,
George Tingsley wrote:
PTFE can be used on the threads but never on the olive

Why? PTFE tape in practice is little different from a sealing compound. It
may not be necessary, but just what harm does it do?

--
*Friends help you move. Real friends help you move bodies.

Dave Plowman London SW
To e-mail, change noise into sound.

Andy Burns wrote:
Mungo wrote:

I haven't used the new Monsoon 3 bar shower pump yet but its my first
exposure to push fittings and I must admit to being quite impressed

My (lesser powered) shower pump can on occasion squeeze a trickle of
water out of it's push fittings :-(

Interesting Andy. In the blurb it said to make sure the copper pipe was
spotlessly clean and without visible flaws.

I've seated the new pump in a plastic tray so that I can catch any
slight
leaks. If it does nothing else then at least it ought to alert me of a
problem.
Next trick is to add a liquid sensor into the tray to ring some sort of
audible
alarm.

Mungo

The message
from "." contains these words:

why call it a /compression/ joint then ? in your world it would be
called a deformation joint which it isn't, it's a /compression/ joint.
methinks you're splitting hairs, why is anyones guess but if the
copper *tube* /deforms/ the joint is and will be defective.

If I show you a bit of copper pipe with a narrow neck in it, would you
say that was deformed?

'Cos that's what it looks like if you cut the olive off after taking
apart a correctly assembled compression joint.

--
Skipweasel
Pay no attention to that man behind the curtain.

In article .com,
George Tingsley wrote:
picture of what will happen if you over tighten a compression fitting
http://www.calormarineshop.co.uk/boa...on_fitting.htm

Interesting they reckon finger tight on a dry 1/2" fitting then 1 1/4
turns. Seems more likely than the less than one turn or so spouted on here.

--
*It was recently discovered that research causes cancer in rats*

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 09 May 2006 19:32:54 +0100 someone who may be "Dave Plowman
(News)" wrote this:-

Interesting they reckon finger tight on a dry 1/2" fitting then 1 1/4
turns. Seems more likely than the less than one turn or so spouted on here.

I turn them until they feel right to me and have yet to have one
fail spectacularly. I have had to tighten the odd one up a little
more though.

I know it is tempting fate to type that:-)


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

In article ,
G.W. Walker wrote:
I've happily used PTFE on olives in the past as well,
but I can see how it might not create a perfect seal.
Unlikely a sealing compound, PTFE isn't liquid, and so
there's a chance that as you tighten the joint, the
PTFE will rip and you'll end up with PTFE around most
of the olive, but with a gap somewhere that could allow
a small leak.

So no different from a paste, etc? That will also rub off from high spots.

--
*I speak fluent patriarchy but it's not my mother tongue

Dave Plowman London SW
To e-mail, change noise into sound.

In article , "Dave Plowman (News)"
wrote:

why call it a /compression/ joint then ? in your world it would be
called a deformation joint which it isn't, it's a /compression/ joint.
methinks you're splitting hairs, why is anyones guess but if the
copper *tube* /deforms/ the joint is and will be defective.

Not so. I've taken many apart, which after removing the olive, show
clear signs of the pipe being indented under where the olive was. And
non of them leaked. If you've not seen this I'd say you have little
experience.

The indentation of the pipe makes me to wonder if replacing old olives
when re-using compression joints might not always be a good thing. I'm
wondering what happens if the new olive doesn't line up exactly with the
groove created by the old one, this could lead to a much shorter area of
tight contact with the pipe and perhaps a less reliable seal. I've not
had much experience with plumbing so I'm not trying to put forward a
case for or against replacing olives, just looking for advice. The
compression joints I've made invariably leaked slightly to start with
but sealed OK after a bit more tightening. I'll be replacing quite a few
radiator valves with TRVs soon so I'd welcome any opinions on this from
the experts.

--
Mike Clarke

Dave Plowman (News) wrote:
In article . com,
George Tingsley wrote:
PTFE can be used on the threads but never on the olive

Why? PTFE tape in practice is little different from a sealing compound. It
may not be necessary, but just what harm does it do?


Ok never say never
But as Calor say in their web page a compression fitting with pipe
olive coupling and nut in perfect condition should not have any gunk
applied to interfere with the mating surface or contaminate the water
or gas supply
I once went to a gas fire that was not working when I dismantled it I
removed a 6 inch length of ptfe tape that was blocking the jet how that
got inside the pipe only God knows

Never in this case means best working practices people new to plumbing
should be aware that compression fittings were never designed to need
additional sealing around the olive and should avoid making joins like
the top picture as routine
http://www.calormarineshop.co.uk/boa...on_fitting.htm

But sooner or later you will encounter the stopcock buried under
kitchen cabinets or the elec shower with only nut-olive protruding out
of a tiled wall which will leak and be impractical to replace
Then you can try ptfe or boss white to affect a cure
I keep a tube of Hermetite instant gasket in the toolbox for such
bodgery

--
*Friends help you move. Real friends help you move bodies.

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
In article .com,
George Tingsley wrote:
picture of what will happen if you over tighten a compression fitting
http://www.calormarineshop.co.uk/boa...on_fitting.htm

Interesting they reckon finger tight on a dry 1/2" fitting then 1 1/4
turns. Seems more likely than the less than one turn or so spouted on here.

The is no torque guide listed from compression fitting manufactures
there are also different shapes of olives both copper and brass which
in theory need a different amount of force to affect a satisfactory
seal
Buy an isolating valve and length of copper pipe from Homebase as many
diyers may do the supplied olives are the worst I have ever seen and
the pipe is the softest I have ever come across
even light pressure will push the olive deep into the pipe and make a
watertight seal impossible
3/4 of a turn is a good starting point and works for most fittings
try it

--
*It was recently discovered that research causes cancer in rats*

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Dave Plowman (News) wrote:
In article ,
G.W. Walker wrote:
I've happily used PTFE on olives in the past as well,
but I can see how it might not create a perfect seal.
Unlikely a sealing compound, PTFE isn't liquid, and so
there's a chance that as you tighten the joint, the
PTFE will rip and you'll end up with PTFE around most
of the olive, but with a gap somewhere that could allow
a small leak.

So no different from a paste, etc? That will also rub off from high spots.

Who knows, TBH? My thinking was that a paste has almost
no mechanical strength, and will get evenly smeared,
but that tape could resist spreading due to its own
strength, but I'll happily admit that this is utter
conjecture on my part.

Sounds like a nice 4th year project for an engineering
student ;-)

G.

George Tingsley wrote:

picture of what will happen if you over tighten a compression fitting
http://www.calormarineshop.co.uk/boa...on_fitting.htm

Since a picture is worth a thousand words anyone else agree with me
that
the cut-away picture on this web site ought to go in the FAQ (if it
isn't there
already - haven't checked)?

Mungo

Mungo wrote:
George Tingsley wrote:
picture of what will happen if you over tighten a compression fitting
http://www.calormarineshop.co.uk/boa...on_fitting.htm

Since a picture is worth a thousand words anyone else agree with me
that the cut-away picture on this web site ought to go in the FAQ

If copying these things is OK, yes, it could help people.

"George Tingsley" wrote in message
ups.com...

Redeye wrote:
after a rather more eventful weekend than i was hoping for, i'm hoping
somebody can explain this....

i finished plumbing in everything in my new bathroom a couple of weeks
ago. no real problems and all went quite well. so, i was a bit
surprised to be woken at 1am on saturday to the sound of water running
and a hysterical girlfriend. it appears that one of the compression
joints has spontaneously exploded, allowing mains pressure water to go
everywhere. fortunately no real damage done, just a lot of mopping up
to do downstairs.

the bit i don't understand is why this joint went so suddenly. here's
the facts :
You did not tighten it enough
for 15mm pipe if you tighten the nut as much as you can by hand and
then tighten by a further 3/4 of a complete turn
if it should weep you can tighten by another 1/8 turn
Beware of being told that you cannot over tighten compression fittings
thats a guaranteed way of making them leak
PTFE can be used on the threads but never on the olive

Wrapping PTFE on the threads of a compression joint serves no purpose
whatsoever. In fact a lot of it may prevent the nut being screwed fully
home.

"George Tingsley" wrote in message
oups.com...

Dave Plowman (News) through a haze of senile flatulence wrote:
In article . com,
George Tingsley wrote:
PTFE can be used on the threads but never on the olive

Why? PTFE tape in practice is little different from a sealing compound.
It
may not be necessary, but just what harm does it do?


Ok never say never
But as Calor say in their web page a compression fitting with pipe
olive coupling and nut in perfect condition should not have any gunk
applied

George, you have got to take into account some of them here are not that
bright. Richard here has been told on numerous occasions on how to use
compression joints, but still comes out with the same crap.

Chris Bacon wrote:

Mungo wrote:
George Tingsley wrote:
picture of what will happen if you over tighten a compression fitting
http://www.calormarineshop.co.uk/boa...on_fitting.htm

Since a picture is worth a thousand words anyone else agree with me
that the cut-away picture on this web site ought to go in the FAQ

If copying these things is OK, yes, it could help people.

Put the link into the faq, not necessarily the whole picture.

Mungo

Doctor Drivel wrote:
"George Tingsley" wrote in message
ups.com...

Redeye wrote:
after a rather more eventful weekend than i was hoping for, i'm hoping
somebody can explain this....

i finished plumbing in everything in my new bathroom a couple of weeks
ago. no real problems and all went quite well. so, i was a bit
surprised to be woken at 1am on saturday to the sound of water running
and a hysterical girlfriend. it appears that one of the compression
joints has spontaneously exploded, allowing mains pressure water to go
everywhere. fortunately no real damage done, just a lot of mopping up
to do downstairs.

the bit i don't understand is why this joint went so suddenly. here's
the facts :
You did not tighten it enough
for 15mm pipe if you tighten the nut as much as you can by hand and
then tighten by a further 3/4 of a complete turn
if it should weep you can tighten by another 1/8 turn
Beware of being told that you cannot over tighten compression fittings
thats a guaranteed way of making them leak
PTFE can be used on the threads but never on the olive

Wrapping PTFE on the threads of a compression joint serves no purpose
whatsoever. In fact a lot of it may prevent the nut being screwed fully
home.

Wrong im sorry to say
Having now read all the massages in this subject
It appears to me that most of the regular experts?
are talking out of their posteriors and even if I clam to have been a
plumber for 50 years why should anyone believe me over Mr Drivel or
Plowman?

I had a rummage in my fittings box and turned up a few old carded
compression fittings
A few facts quoted from the manufactures which you would hope know more
about their products then a diyforum

By Opella
Usual cleaning info
Apply PTFE tape to male fitting threads only
Hand tighten nut then spanner tighten nut further 1/2 turn 15mm 3/4
turn 22mm
DO NOT OVERTIGHTEN- in large print

By Oracstar
Usual cleaning info
Apply Vaseline to threads
Screw on cap nut until finger tight
Mark capnuts and pipe with pencil
Tighten a further 1/2 to one full turn past the marks
Beware DO NOT OVERTIGHTEN- again in large print
This fitting was marked 1/2 inch so could pre-date ptfe tape Vaseline
was used years ago to lubricate threads

Go into any diy store that sales carded plumbing fittings and read the
instructions printed on the reverse
I would be very surprised if anything has changed

In article .com,
George Tingsley wrote:
But as Calor say in their web page a compression fitting with pipe
olive coupling and nut in perfect condition should not have any gunk
applied to interfere with the mating surface or contaminate the water
or gas supply

Calor show the entire pipe and olive coated with red Hermetite or
something and suggest this prevents the pipe being seated correctly on the
fitting shoulder. Wrapping PTFE round the olive doesn't.

I once went to a gas fire that was not working when I dismantled it I
removed a 6 inch length of ptfe tape that was blocking the jet how that
got inside the pipe only God knows

Probably a 'plumber' making work for a 'mate' later. There's no way it
could get inside the pipe from being wrapped round an olive - unless the
pipe was cut by dribble's hacksaw at his usual 45 degrees.

--
*Time is the best teacher; unfortunately it kills all its students.

Dave Plowman London SW
To e-mail, change noise into sound.

In article .com,
George Tingsley wrote:
But sooner or later you will encounter the stopcock buried under
kitchen cabinets or the elec shower with only nut-olive protruding out
of a tiled wall which will leak and be impractical to replace
Then you can try ptfe or boss white to affect a cure
I keep a tube of Hermetite instant gasket in the toolbox for such
bodger

Fernox LX is the daddy for this.

--
*The sooner you fall behind, the more time you'll have to catch up *

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 09 May 2006 14:50:53 +0100, Dave Plowman (News) wrote:

In article ,
. wrote:
why call it a /compression/ joint then ? in your world it would be
called a deformation joint which it isn't, it's a /compression/ joint.
methinks you're splitting hairs, why is anyones guess but if the
copper *tube* /deforms/ the joint is and will be defective.

Not so. I've taken many apart, which after removing the olive, show clear
signs of the pipe being indented under where the olive was. And non of
them leaked. If you've not seen this I'd say you have little experience.

Agreed. Given that, invariably, any joint that is undone you find the
olive crimped onto the pipe.



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

"George Tingsley" wrote in message
oups.com...

Doctor Drivel wrote:
"George Tingsley" wrote in message
ups.com...

Redeye wrote:
after a rather more eventful weekend than i was hoping for, i'm hoping
somebody can explain this....

i finished plumbing in everything in my new bathroom a couple of weeks
ago. no real problems and all went quite well. so, i was a bit
surprised to be woken at 1am on saturday to the sound of water running
and a hysterical girlfriend. it appears that one of the compression
joints has spontaneously exploded, allowing mains pressure water to go
everywhere. fortunately no real damage done, just a lot of mopping up
to do downstairs.

the bit i don't understand is why this joint went so suddenly. here's
the facts :
You did not tighten it enough
for 15mm pipe if you tighten the nut as much as you can by hand and
then tighten by a further 3/4 of a complete turn
if it should weep you can tighten by another 1/8 turn
Beware of being told that you cannot over tighten compression fittings
thats a guaranteed way of making them leak
PTFE can be used on the threads but never on the olive

Wrapping PTFE on the threads of a compression joint serves no purpose
whatsoever. In fact a lot of it may prevent the nut being screwed fully
home.

Wrong im sorry to say

You are talking though your rear end boy. I think you should stick to
drains. Look at the the the cutaways you posted. Read what I wrote.

Having now read all the massages in this subject
It appears to me that most of the regular experts?
are talking out of their posteriors and even if I clam to have been a
plumber for 50 years why should anyone believe me over Mr Drivel or
Plowman?

Plowman is a senile idiot, That is clear. He never serviced his boier fro
12 years and advised everyone else to do the same - a madman. I am a
heating engineer. I don't do drains.

I had a rummage in my fittings box and turned up a few old carded
compression fittings
A few facts quoted from the manufactures which you would hope know more
about their products then a diyforum

By Opella
Usual cleaning info
Apply PTFE tape to male fitting threads only
Hand tighten nut then spanner tighten nut further 1/2 turn 15mm 3/4
turn 22mm
DO NOT OVERTIGHTEN- in large print

PTFE does nothing to make a seal on the compresion nut threads. If there is
aleak it will leak out beteen the pipe and nut which has no threaded joint
at all. Look at the fitting and how it is made up. Look at the cutaways.

In article ,
Mike Clarke wrote:
Not so. I've taken many apart, which after removing the olive, show
clear signs of the pipe being indented under where the olive was. And
non of them leaked. If you've not seen this I'd say you have little
experience.

The indentation of the pipe makes me to wonder if replacing old olives
when re-using compression joints might not always be a good thing. I'm
wondering what happens if the new olive doesn't line up exactly with the
groove created by the old one, this could lead to a much shorter area of
tight contact with the pipe and perhaps a less reliable seal.

I should point out that not all show obvious signs of indents - just some.

But if you're simply re-making a compression fitting, there's no need to
change the olive.

--
*One nice thing about egotists: they don't talk about other people.

Dave Plowman London SW
To e-mail, change noise into sound.

In article .com,
George Tingsley wrote:
Wrong im sorry to say
Having now read all the massages in this subject
It appears to me that most of the regular experts?
are talking out of their posteriors and even if I clam to have been a
plumber for 50 years why should anyone believe me over Mr Drivel or
Plowman?

I had a rummage in my fittings box and turned up a few old carded
compression fittings
A few facts quoted from the manufactures which you would hope know more
about their products then a diyforum

By Opella
Usual cleaning info
Apply PTFE tape to male fitting threads only
Hand tighten nut then spanner tighten nut further 1/2 turn 15mm 3/4
turn 22mm
DO NOT OVERTIGHTEN- in large print

You earlier quoted the Calor site. Go back to it and see its advice on how
far to tighten a 15mm fitting...;-)

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*Income tax service - We‘ve got what it takes to take what you've got.

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:

In article .com,
George Tingsley wrote:

I had a rummage in my fittings box and turned up a few old carded
compression fittings
A few facts quoted from the manufactures which you would hope know more
about their products then a diyforum

By Opella
Usual cleaning info
Apply PTFE tape to male fitting threads only
Hand tighten nut then spanner tighten nut further 1/2 turn 15mm 3/4
turn 22mm
DO NOT OVERTIGHTEN- in large print

You earlier quoted the Calor site. Go back to it and see its advice on how
far to tighten a 15mm fitting...;-)

That was a reply to Mr Drivel who says you should not use ptfe tape on
fitting threads and is now drivelling on about leaks from threads I
don't think its worth the effort replying to him he must be your
DIYing brother
You on the other hand don't seem to be able to accept that over
tightening is bad news on compression fittings
Here a few more web pages that contradict your earlier advice that you
should

USE OPEN ENDED SPANNERS AND TIGHTEN THEM TILL THEY GROAN

http://www.technosolution.co.uk/diy/...coppercomp.htm
http://www.diydoctor.org.uk/projects...ion_joints.htm

So over to you again feel free to point me to any source that agrees
with your advice
or would you now like to admit that you don't know what you are
talking about


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*Income tax service - We've got what it takes to take what you've got.

Dave Plowman London SW
To e-mail, change noise into sound.

George Tingsley wrote:
Dave Plowman (News) wrote:
[ snip ]
You on the other hand don't seem to be able to accept that over
tightening is bad news on compression fittings
Here a few more web pages that contradict your earlier advice that you
should

USE OPEN ENDED SPANNERS AND TIGHTEN THEM TILL THEY GROAN

[snip]

It's sort of possible that DP was referring to doing up fittings
until they make a sort of squeak, which clean brass on brass does
when under load. This "technique" isn't to be relied on, though.

It's always possible, having tightened the joint, to undo it and
examine the olive/pipe, doing the fitting up again with a small
extra tweak after (assuming everything looks OK).

"George Tingsley" wrote in message
oups.com...

Dave Plowman (News) through a haze of senle flatulence wrote:

In article .com,
George Tingsley wrote:

I had a rummage in my fittings box and turned up a few old carded
compression fittings
A few facts quoted from the manufactures which you would hope know more
about their products then a diyforum

By Opella
Usual cleaning info
Apply PTFE tape to male fitting threads only
Hand tighten nut then spanner tighten nut further 1/2 turn 15mm 3/4
turn 22mm
DO NOT OVERTIGHTEN- in large print

You earlier quoted the Calor site. Go back to it and see its advice on
how
far to tighten a 15mm fitting...;-)

That was a reply to Mr Drivel who says you should not use ptfe tape on
fitting threads and is now drivelling on about leaks from threads I
don't think its worth the effort replying to him he must be your
DIYing brother

I am full pro. You come across as a bodger. You certainly don't fully
understand how a compression joint makes its seal.

I repeat, wrapping PTFE on a parallel thread on a compression fitting body
that a compression nut runs along, serves no purpose whatsoever except waste
PTFE tape.

"George Tingsley" wrote in message
oups.com...

http://www.diydoctor.org.uk/projects...ion_joints.htm

This says:

"Wherever possible, use a layer of PTFE tape around the thread of the
compression fitting. This tape will be pushed into the thread by the
tightening of the nut and seal any overlarge gaps within the union of the
threads. "

Again....wrapping PTFE on a parallel thread on a compression fitting body
that a compression nut runs along, serves no purpose whatsoever except waste
PTFE tape. The parallel thread is for the compression nut to run along. It
is not a thread that makes a seal at all, it is there for the nut to run
along and tighten onto the olive.

PTFE does nothing to make a seal on the compression nut parallel threads.
The nut has a thread one end and a hole the other for the pipe to run
through. None of the ends of the nut, threaded or not, make a seal. It is
possible to make a seal on the parallel thread by using Loctite, but if
there is a leak it will just leak out between the pipe and nut at the other
end, which has no threaded joint at all.

The message ews.net
from "Doctor Drivel" contains these words:

"Wherever possible, use a layer of PTFE tape around the thread of the
compression fitting. This tape will be pushed into the thread by the
tightening of the nut and seal any overlarge gaps within the union of the
threads. "

Can't see why it matters whether the threads are sealed or not. They're
nothing to do with the hermeticity of the union.

--
Skipweasel
Pay no attention to that man behind the curtain.