Sealing compound for threaded connectors

29 Mar 2007
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United Kingdom
I'll soon be replumbing a basin with new taps and connectors . When connecting a new brass (15mm by 1/2") MI coupler to an existing iron water pipe , what sealing compound would you advise ?

Please bear in mind that the threads in the iron socket are not brand new - they will have the remains of the ancient sealing compound ( hemp and Boss White perhaps ) in them , although I'll remove as much of it as I can .

Screwfix offer me Loctite 55 Pipe Seal Cord , Liquid PTFE in gel form , Pipe Sealant aka Pipe Thread Seal , Loctite Pipe Sealant , Loctite Thread Sealant Stick , Hawk White jointing compound , Water Hawk jointing compound and good old PTFE tape . Any comments please ?

And if whatever I choose doesn't work perfectly , is it too much of a bodge to wipe a bit of Fernox LS-X around the outside of the joint afterwards ?
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I'm not sure if this is the right way but

I've had the same issues with my own DIY plumbing. I have used LS-X on the threads as sealer and have not had a single leak from a copper to iron fitting yet
Warm the socket to soften the goo and clean with a wire pipe cleaing brush - or your wife's toothbrush, at a pinch.
Tape should be fine, but if you're worried there's no law against putting a little Ls-x in there as well.
Thanks for both replies - reassuring and helpful .
I wonder why so many different compounds are available , though . There must be demand for them - so what advantages do they offer ?
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in a nutshell ;) ........old ways/ new ways .............wholesome water/non wholesome water in the pipes
On subject of sealants has anybody heard of Chesterton Gold End paste as i would dearly like to get hold of some , its usually in 250 gram tubes or could be mililitre tubes . cheers mark
Nearest I`ve used was Dinger Bell-end paste.........used it while welding :eek:
Nige F said:
Nearest I`ve used was Dinger Bell-end paste.........used it while welding :eek:

Where can i get some bell end paste? Toothpaste is to gritty and stings.
toothpaste is for Mast....ICATION.......RU Dylsexic :eek: :LOL:

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