[Ron Lowe]

Hi, all.

I've just installed another shower mixer ( an expensive Grohe one ), and as
per usual, the connections to it are 1/2" BSP parallel.

The male BSP - compression adapters I obtained are a rather loose fit
before we apply thread tape, and being a parallel ( as opposed to
BSP-taper ) thread, they don't tighten up as you spin them on. They bottom
out.

On goes the PTFE tape. In order to make even a vaguely 'tight' fit, I need
to use what I consider a huge amount of PTFE tape. Something like 10 wraps
or more. The threads are almost no longer visible beneath the tape! Then
we tighten it up. Again, since it's a parallel thread, it doesn't get
satisfyingly tighter as we do it up, it just continues at the same torque
until it bottoms out. The more layers of PTFE, the higher the tightening
torque.

This kind of works ( in as much as it usually remains watertight ), but is
most un-satisfying.
One of my connections then developed a 'weep', and I had to re-make it.
Naturally, it was the most awkward one to get at.
All in all, I'm fair scunnered of the "PTFE tape and BSP-Parallel threads"
connection.
So I'd like to look for an alternative, perhaps a jointing compound.

What I'd like to know is this:

What is the correct use of jointing compounds like LSX?
Is it used *instead* of PTFE tape?
How would it perform in the scenario I described, where a male BSP-P fitting
is a fairly loose fit into the female? Is the viscosity enough to fill
the helical leak path along the thread? Does it 'set' and provide mechanical
strength as well as a seal? Or do I rely on bottoming out the fitting to
loose the 'wobble', and let the LSX fill the helical leak path?

Or is it not suitable for this application?

--
Ron

[zedbun]

Why not try to use an old fashioned solution such as hemp and jointing
compound. The threads of hemp easily stop any play. When they get damp
they swell up and together with the sealing compound ensure the joint
is water tight. I have always used this on coarser threads and when
PTFE is not enough and have been very satisfied.

Good luck !

[Andy Hall]

On 2006-11-05 18:22:37 +0000, "Ron Lowe"
said:

Hi, all.

I've just installed another shower mixer ( an expensive Grohe one ),
and as per usual, the connections to it are 1/2" BSP parallel.

The male BSP - compression adapters I obtained are a rather loose fit
before we apply thread tape, and being a parallel ( as opposed to
BSP-taper ) thread, they don't tighten up as you spin them on. They
bottom out.

On goes the PTFE tape. In order to make even a vaguely 'tight' fit, I
need to use what I consider a huge amount of PTFE tape. Something like
10 wraps or more. The threads are almost no longer visible beneath the
tape! Then we tighten it up. Again, since it's a parallel thread, it
doesn't get satisfyingly tighter as we do it up, it just continues at
the same torque until it bottoms out. The more layers of PTFE, the
higher the tightening torque.

This kind of works ( in as much as it usually remains watertight ), but
is most un-satisfying.
One of my connections then developed a 'weep', and I had to re-make it.
Naturally, it was the most awkward one to get at.
All in all, I'm fair scunnered of the "PTFE tape and BSP-Parallel
threads" connection.
So I'd like to look for an alternative, perhaps a jointing compound.

What I'd like to know is this:

What is the correct use of jointing compounds like LSX?
Is it used *instead* of PTFE tape?
How would it perform in the scenario I described, where a male BSP-P
fitting is a fairly loose fit into the female? Is the viscosity
enough to fill the helical leak path along the thread? Does it 'set'
and provide mechanical strength as well as a seal? Or do I rely on
bottoming out the fitting to loose the 'wobble', and let the LSX fill
the helical leak path?

Or is it not suitable for this application?

I've had this situation with taps such as Grohe and Hansgrohe, and for
that matter, with large fittings on hot water cylinders and certain
types of radiator tail and radiator.

I have used PTFE sealing liquid and it works effectively. Paint it on
the male thread, leave it a short while to dry slightly and screw it in.

Two other alternatives:

- The age old hemp and Boss White (or green for potable) is very effective.

- Gas type PTFE tape. This is thicker than the mimsy plumbing stuff
and doesn't have the same tendency to bunch up or be cut by the thread
of the fitting.

[John Rumm]

Ron Lowe wrote:

On goes the PTFE tape. In order to make even a vaguely 'tight' fit, I need
to use what I consider a huge amount of PTFE tape. Something like 10 wraps
or more. The threads are almost no longer visible beneath the tape! Then
we tighten it up. Again, since it's a parallel thread, it doesn't get
satisfyingly tighter as we do it up, it just continues at the same torque
until it bottoms out. The more layers of PTFE, the higher the tightening
torque.

This kind of works ( in as much as it usually remains watertight ), but is
most un-satisfying.

The trick with the ptfe is to apply a number of twists overlapping and
increasing in thickness toward the rear of the fitting (you can twist
the tape to make a narrower strand of it if needs be), so you have a
cone shape to it. That way it gets tighter as you tighten.

Having said that, on large fittings (cylinder connections for example) I
prefer hemp and boss white.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

[Dave Plowman (News)]

In article ,
Ron Lowe wrote:
What I'd like to know is this:

What is the correct use of jointing compounds like LSX?
Is it used *instead* of PTFE tape?

I found it very successful on a plastic thread connector to a cistern
where the pipe was copper with a tap connector on the end and perhaps not
perfectly lined up.

--
*Out of my mind. Back in five minutes.

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

[Skokiaan]

I use this stuff (Pipe seal):

http://www.screwfix.com/app/sfd/cat/...03796&id=12693

(But don't use it on immersion heater threads, you'll never get the
bloody thing out again!)

Chris



















Ron Lowe wrote:
Hi, all.

I've just installed another shower mixer ( an expensive Grohe one ), and as
per usual, the connections to it are 1/2" BSP parallel.

The male BSP - compression adapters I obtained are a rather loose fit
before we apply thread tape, and being a parallel ( as opposed to
BSP-taper ) thread, they don't tighten up as you spin them on. They bottom
out.

On goes the PTFE tape. In order to make even a vaguely 'tight' fit, I need
to use what I consider a huge amount of PTFE tape. Something like 10 wraps
or more. The threads are almost no longer visible beneath the tape! Then
we tighten it up. Again, since it's a parallel thread, it doesn't get
satisfyingly tighter as we do it up, it just continues at the same torque
until it bottoms out. The more layers of PTFE, the higher the tightening
torque.

This kind of works ( in as much as it usually remains watertight ), but is
most un-satisfying.
One of my connections then developed a 'weep', and I had to re-make it.
Naturally, it was the most awkward one to get at.
All in all, I'm fair scunnered of the "PTFE tape and BSP-Parallel threads"
connection.
So I'd like to look for an alternative, perhaps a jointing compound.

What I'd like to know is this:

What is the correct use of jointing compounds like LSX?
Is it used *instead* of PTFE tape?
How would it perform in the scenario I described, where a male BSP-P fitting
is a fairly loose fit into the female? Is the viscosity enough to fill
the helical leak path along the thread? Does it 'set' and provide mechanical
strength as well as a seal? Or do I rely on bottoming out the fitting to
loose the 'wobble', and let the LSX fill the helical leak path?

Or is it not suitable for this application?

--
Ron

[Christian McArdle]

What is the correct use of jointing compounds like LSX?
Is it used *instead* of PTFE tape?

I've recently had to do the same job. I eventually gave up on PTFE and used
LS-X and the ceiling hasn't come down yet!

I know you are probably not supposed to, but I just applied the LS-X over
the top of the PTFE, as I couldn't be bothered to unwind it all! I didn't
quite bottom it out.

What I did probably wasn't the official solution, but it did get my shower
working. I also applied the same system to my leaking water softener
connections, which had the same issue complicated by the fact that the male
fitting was plastic.

Christian.

[The Medway Handyman]

Ron Lowe wrote:
Hi, all.

I've just installed another shower mixer ( an expensive Grohe one ),
and as per usual, the connections to it are 1/2" BSP parallel.

The male BSP - compression adapters I obtained are a rather loose
fit before we apply thread tape, and being a parallel ( as opposed to
BSP-taper ) thread, they don't tighten up as you spin them on. They
bottom out.

Would this be any good? Loctite 55 Pipe Seal Cord 50m
http://www.screwfix.com/app/sfd/cat/...12714&id=42142


--
Dave
The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257