Loctite 577

[Gyn_Paul]

This is one for the professional plumbers like Punch I

suppose......Have any of you experience of making joints with Loctite

577?

I'm plumbing in rads and am using 1/2" male-male brass elbows into the

1/2" female rad valves. they need to end up angled slightly back

towards the wall. Normally I'd use hemp and Boss White and a sort of

add-subtract tighten/loosen process to end up with a tight joint set at

the right angle.  Without anything on the thread it is in the

right place when just over finger tight (but no way would it go

round a further 350 degrees). Will Loctite make a good water-tight seal

at just over finger tight?  If it does, would you regard this as

good plumbing practice? I realise I've done all 8 rad valve cores with

the stuff, too; but at least with these they are screwed in with a

giant alan key and an extender bar so that they are just shy of

stripping the thread so the sealing properties of Loctite 577 are

probably academic! but with the other bits (esp. brass ones) it would

be good to know from other's experiences how tight one needs to be.

It will be the usual 1 - 2 bar sealed CH system.

paul

[LesFlamands]

Most of these thread sealing compounds work fine. Even if they claim that they can be put under pressure immediately, I find they are best left for 24 hours which is generally not a problem when installing central heating.

[Jc]

Over the years I've used Boss White or similar and string,PTFE tape,Loctite but what I tend to use now is Fernox LSX(bit like toothpaste) and you don't have to overtighten-putting an extension on the end of your allen key is asking for trouble-it should not need to be that tight.There is an a French equivalent to Fernox(a pale grey paste)but its not as good.One of the advantages of the  Fernox is that you can put a thin smear on any olives to improve their sealing even more.