A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened it up
and found it was what it initially seemed to be - not done up properly
to begin with and a bit of dirt/scale/slight scoring allowing the
tiniest moistness. So I wrapped the olive neatly with some PTFE tape,
tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

--
Rod

On 01/03/2015 11:58, polygonum wrote:
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened it up
and found it was what it initially seemed to be - not done up properly
to begin with and a bit of dirt/scale/slight scoring allowing the
tiniest moistness. So I wrapped the olive neatly with some PTFE tape,
tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

I've had similar experiences and thoughts. Gas tape is so much better IMO.

21p as opposed to 50p. Spose it might matter if you use hundreds of rolls.

--
Dave - The Medway Handyman www.medwayhandyman.co.uk

On 01/03/2015 12:14, The Medway Handyman wrote:
On 01/03/2015 11:58, polygonum wrote:
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened it up
and found it was what it initially seemed to be - not done up properly
to begin with and a bit of dirt/scale/slight scoring allowing the
tiniest moistness. So I wrapped the olive neatly with some PTFE tape,
tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

I've had similar experiences and thoughts. Gas tape is so much better IMO.

21p as opposed to 50p. Spose it might matter if you use hundreds of rolls.

And 12m as opposed to 5m. Still at the ignorable end of the scale
unless, as you say, using miles of it.

--
Rod

On 01/03/2015 12:54, polygonum wrote:
On 01/03/2015 12:14, The Medway Handyman wrote:
On 01/03/2015 11:58, polygonum wrote:
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened it up
and found it was what it initially seemed to be - not done up properly
to begin with and a bit of dirt/scale/slight scoring allowing the
tiniest moistness. So I wrapped the olive neatly with some PTFE tape,
tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

I've had similar experiences and thoughts. Gas tape is so much better
IMO.

21p as opposed to 50p. Spose it might matter if you use hundreds of
rolls.

And 12m as opposed to 5m. Still at the ignorable end of the scale
unless, as you say, using miles of it.


I bought a pack of (I think) 10 rolls of gas PTFE a few years ago for
not very much when SF were doing an offer. It's brilliant stuff - I've
not used 'ordinary' PTFE ever since. Because it's thicker, you need less
of it - and it doesn't get shredded by the threads like the regular
stuff does.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On 01/03/2015 13:20, Roger Mills wrote:
On 01/03/2015 12:54, polygonum wrote:
On 01/03/2015 12:14, The Medway Handyman wrote:
On 01/03/2015 11:58, polygonum wrote:
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened
it up
and found it was what it initially seemed to be - not done up properly
to begin with and a bit of dirt/scale/slight scoring allowing the
tiniest moistness. So I wrapped the olive neatly with some PTFE tape,
tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering
why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

I've had similar experiences and thoughts. Gas tape is so much better
IMO.

21p as opposed to 50p. Spose it might matter if you use hundreds of
rolls.

And 12m as opposed to 5m. Still at the ignorable end of the scale
unless, as you say, using miles of it.


I bought a pack of (I think) 10 rolls of gas PTFE a few years ago for
not very much when SF were doing an offer. It's brilliant stuff - I've
not used 'ordinary' PTFE ever since. Because it's thicker, you need less
of it - and it doesn't get shredded by the threads like the regular
stuff does.

I'm inclined to agree, the only possible advantage I can see for the
thinner is that the "shredding" might allow it to fill up threads on a
male item a little more effectively. Also you have a little more control
if there is an unthreaded pin-bush clearance to fill.

I think the gas one does not produce static, which I guess if there is gas
about might not be very nice. Of course its not pure ptfe, as it contains a
semi conductive part.
I can well remember when emi decided to use ptfe liners in their audio
cassettes, most people started hearing clicks on their tapes, and a good
fast rewind made it most likely you would get a shock taking it out of its
machine.

Very good stuff to use to make static electricity generators with, if a
little expensive. I blame the ions.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"polygonum" wrote in message
...
A little while ago I posted about an MDPE weeping connection - thanks for
responses.

Having prepared for destroyed olive, no insert or whatever, opened it up
and found it was what it initially seemed to be - not done up properly to
begin with and a bit of dirt/scale/slight scoring allowing the tiniest
moistness. So I wrapped the olive neatly with some PTFE tape, tightened it
up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness, not
flying away with static, easy to wrap neatly. Now I am wondering why they
bother making non-gas PTFE. Is there any good reason? Or is it simply a
cheaper and crappier product without other merit? (Not that Toolstation's
finest was expensive!)

--
Rod

On 01/03/2015 13:40, newshound wrote:
On 01/03/2015 13:20, Roger Mills wrote:
On 01/03/2015 12:54, polygonum wrote:
On 01/03/2015 12:14, The Medway Handyman wrote:
On 01/03/2015 11:58, polygonum wrote:
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened
it up
and found it was what it initially seemed to be - not done up properly
to begin with and a bit of dirt/scale/slight scoring allowing the
tiniest moistness. So I wrapped the olive neatly with some PTFE tape,
tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering
why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

I've had similar experiences and thoughts. Gas tape is so much better
IMO.

21p as opposed to 50p. Spose it might matter if you use hundreds of
rolls.

And 12m as opposed to 5m. Still at the ignorable end of the scale
unless, as you say, using miles of it.


I bought a pack of (I think) 10 rolls of gas PTFE a few years ago for
not very much when SF were doing an offer. It's brilliant stuff - I've
not used 'ordinary' PTFE ever since. Because it's thicker, you need less
of it - and it doesn't get shredded by the threads like the regular
stuff does.

I'm inclined to agree, the only possible advantage I can see for the
thinner is that the "shredding" might allow it to fill up threads on a
male item a little more effectively. Also you have a little more control
if there is an unthreaded pin-bush clearance to fill.

In which case you would have thought the thin stuff would be good for gas?

Just an observation (and from watching helpful videos on Youtube), I think
some people reach for the PTFE when it should not be used. I have removed
compression fittings where the PTFE has been used on the threads and on tap
connectors. We need to identify what performs the sealing - and what
provides the clamping force. I guess some people might jump in and say they
use it everywhere as it does no harm.

On 01/03/2015 18:02, DerbyBorn wrote:
Just an observation (and from watching helpful videos on Youtube), I think
some people reach for the PTFE when it should not be used. I have removed
compression fittings where the PTFE has been used on the threads and on tap
connectors. We need to identify what performs the sealing - and what
provides the clamping force. I guess some people might jump in and say they
use it everywhere as it does no harm.

I think it can help to lubricate a thread so it is easier to tighten up
- and probably helps to ensure it can be undone in future. But shouldn't
really be necessary.

--
Rod

In message , polygonum
writes
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened it
up and found it was what it initially seemed to be - not done up
properly to begin with and a bit of dirt/scale/slight scoring allowing
the tiniest moistness. So I wrapped the olive neatly with some PTFE
tape, tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering
why they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

Perhaps it's safe to use with drinking water and the gas one isn't?
--
bert

On 01/03/15 20:14, bert wrote:
In message , polygonum
writes
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened it
up and found it was what it initially seemed to be - not done up
properly to begin with and a bit of dirt/scale/slight scoring allowing
the tiniest moistness. So I wrapped the olive neatly with some PTFE
tape, tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering
why they bother making non-gas PTFE. Is there any good reason? Or is
it simply a cheaper and crappier product without other merit? (Not
that Toolstation's finest was expensive!)

Perhaps it's safe to use with drinking water and the gas one isn't?

Not that I know of.

On 01/03/2015 19:14, polygonum wrote:
On 01/03/2015 18:02, DerbyBorn wrote:
Just an observation (and from watching helpful videos on Youtube), I
think
some people reach for the PTFE when it should not be used. I have removed
compression fittings where the PTFE has been used on the threads and
on tap
connectors. We need to identify what performs the sealing - and what
provides the clamping force. I guess some people might jump in and say
they
use it everywhere as it does no harm.

I think it can help to lubricate a thread so it is easier to tighten up
- and probably helps to ensure it can be undone in future. But shouldn't
really be necessary.

That's exactly why I *do* use it on threaded connections, even
compression joints with an olive. I don't wind it over the olive,
although to be honest I do not believe it would adversely affect the
sealing because the metal to metal contact is at a pressure related to
the yield stress of the brass, copper, or whatever and this is *very*
much higher than the flow stress of PTFE.

It also helps when used liberally on the threads of immersion heaters,
because it fills up the gaps and prevents water penetrating and
depositing limescale. A friend of mine has some which do a lot of work
in his brewery, and need replacing every year or so. This has been much
easier since I trained his fitter to use at least 10 turns.

In message , Tim Watts
writes
On 01/03/15 20:14, bert wrote:
In message , polygonum
writes
A little while ago I posted about an MDPE weeping connection - thanks
for responses.

Having prepared for destroyed olive, no insert or whatever, opened it
up and found it was what it initially seemed to be - not done up
properly to begin with and a bit of dirt/scale/slight scoring allowing
the tiniest moistness. So I wrapped the olive neatly with some PTFE
tape, tightened it up properly, and it is nice and sound.

For the first time, I used gas PTFE tape. Lovely and decent thickness,
not flying away with static, easy to wrap neatly. Now I am wondering
why they bother making non-gas PTFE. Is there any good reason? Or is
it simply a cheaper and crappier product without other merit? (Not
that Toolstation's finest was expensive!)

Perhaps it's safe to use with drinking water and the gas one isn't?

Not that I know of.
From Wiki colours of spools.

White €“ used on NPT threads up to 3/8 inch
Yellow €“ used on NPT threads 1/2 inch to 2 inch, often labeled
"gas tape"
Pink €“ used on NPT threads 1/2 inch to 2 inch
Green €“ oil-free PTFE used on oxygen lines and some specific
medical gasses
Gray €“ contains nickel, anti-seizing, anti-gailling and
anti-corrosion, used for stainless pipes
Copper €“ contains copper granules and is certified as a thread
lubricant but not a sealer

--
bert

On 01/03/2015 18:02, DerbyBorn wrote:
Just an observation (and from watching helpful videos on Youtube), I think
some people reach for the PTFE when it should not be used. I have removed
compression fittings where the PTFE has been used on the threads and on tap
connectors. We need to identify what performs the sealing - and what
provides the clamping force. I guess some people might jump in and say they
use it everywhere as it does no harm.

My policy is to only use PTFE to seal tapered thread, otherwise I avoid
the stuff.

polygonum wrote in
:

On 01/03/2015 18:02, DerbyBorn wrote:
Just an observation (and from watching helpful videos on Youtube), I
think some people reach for the PTFE when it should not be used. I
have removed compression fittings where the PTFE has been used on the
threads and on tap connectors. We need to identify what performs the
sealing - and what provides the clamping force. I guess some people
might jump in and say they use it everywhere as it does no harm.

I think it can help to lubricate a thread so it is easier to tighten
up - and probably helps to ensure it can be undone in future. But
shouldn't really be necessary.


A smear of grease would work as well. This is my usual approach.

On Sunday, March 1, 2015 at 11:58:26 AM UTC, polygonum wrote:
Now I am wondering why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

The only difference is in the density of the tape.

Voids open up in the material when PTFE is stretched, as part of the manufacturing process.

SFAIK, there is no BS for ordinary plumbing PTFE tape (sold by length), while the gas tape is manufactured to some British Gas specification (can't be arsed to look it up). There is an incentive for the manufacturers to stretch the PTFE as much as possible to yield the maximum length of PTFE tape.

With the gas tape, you're buying more PTFE and less hole.

Goretex is stretched PTFE, so for that material the microscopic holes must be large enough to allow water vapour through while keeping water out.

In article ,
wrote:
On Sunday, March 1, 2015 at 11:58:26 AM UTC, polygonum wrote: Now I am
wondering why
they bother making non-gas PTFE. Is there any good reason? Or is it
simply a cheaper and crappier product without other merit? (Not that
Toolstation's finest was expensive!)

The only difference is in the density of the tape.

Voids open up in the material when PTFE is stretched, as part of the
manufacturing process.

SFAIK, there is no BS for ordinary plumbing PTFE tape (sold by length),
while the gas tape is manufactured to some British Gas specification
(can't be arsed to look it up). There is an incentive for the
manufacturers to stretch the PTFE as much as possible to yield the
maximum length of PTFE tape.

Yes, I'm sure the PTFE tape I buy nowadays is much thinner than the stuff I
used 40+ years ago when installing a CH system.

--
From KT24 in Surrey

Using a RISC OS computer running v5.18

On 02/03/2015 14:19, charles wrote:


Yes, I'm sure the PTFE tape I buy nowadays is much thinner than the stuff I
used 40+ years ago when installing a CH system.


That would have been hemp, wouldn't it? g
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On 02/03/2015 14:56, Roger Mills wrote:
On 02/03/2015 14:19, charles wrote:


Yes, I'm sure the PTFE tape I buy nowadays is much thinner than the
stuff I
used 40+ years ago when installing a CH system.


That would have been hemp, wouldn't it? g


Or Oakum :-)


--
Dave - The Medway Handyman www.medwayhandyman.co.uk