tom.harrigan
wibbled on Monday 23 November 2009 00:20

On 20 Nov, 18:41, Tim W wrote:
tom.harrigan
wibbled on Friday 20 November 2009 17:52

My tank takes 3/4" BSPM fittings, but they keep leaking (testing with
air). The trouble is, the fittings don't screw all the way in, so I
basically have to pack them out with loads of PTFE tape to get a seal,
which I'm not happy about. Perhaps that's the way the pros bodge it?

Rocol Threadseal XS.

Basically thick Loctite for potable water, hot and cold. That will do
it...

If the fittings don't screw all the way in, I assume you have a taper BSP
fitting (I don't know - I have compression fittings on my cylinder) in
which case it's usually lots of PTFE or hemp+boss white for non potable
or variations on that theme. Ultimately, you have to fill all of the
space in a partial length on the threads with something.

Personally I'm going to use Threadseal for everything like that - it's
fantastic.

I'd prefer fittings that screw all the way in, but a suitable washer
would work too I suppose. I'm not convinced fibre washers are up to
the job, are they?

Nothing wrong with fibre washers on fittings that are supposed to take
them - it's likely every tap in your house uses one on it's pipe
connector. They are a pretty reliable technology. This assumes that
you'll then be using BSP parallel and both bits have a nice smooth face
to receive the washer?

I'm not up on every variation of random tank fitting so someone else may
have some suggestions too...

HTH

Tim
--
Tim Watts

This space intentionally left blank...

Thanks to Tm and Bruce for your advice. Screwfix stock Loctite 577, so
I got some of that for the BSP male fitting.

Having looked at the data sheet, that looks pretty much like their version
of Threadseal XS. The only difference is that Loctite don't state potable
(or WRAS) approval. Not really an issue with your presumably non potable
connections(?).

Because I have removed
compression fittings several times to get at the joint, I beefed the
compression fittings with some Fernox LS-X.

Fernox LS-X is silicone sealant. It'll work, but for next time, personally I
might be tempted to go with something like Virgin White (PTFE loaded soft
setting white gunk, looks a bit like Boss White) (again non potable).

--
Tim Watts

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