Thread Sealing

[Pete321]

Hi,

Long time lurker, find this forum really interesting, but now have a problem I thought I'd join to seek advice

I'm having a real job sealing a thread for a bath mixer, see photos (you can see the drip forming in the second photo). Got a fair amount of plumbing experience but never had such a PITA with a thread. I've tried PTFE, Jet-Lube V2, PTFE + Jet-Lube V2. I just cannot stop it dripping once water pressure is applied (the left hand one did eventually seem to seal).

Can't help thinking I need to strip it down, clean it all and start again. But what would product/technique would you use for sealing something like this?

Thanks in advance.
Pete.

 

[townfanjon]

I use loctite 55 , bin the ptfe tape . Loctite do a thread sealant , I think its 577 or something like that , @Shaun will be along to confirm

 

[king of pipes]

Loctite 55 is my go to thread sealant bud as you say clean it all down first .kop

Town beat me to it

 

[rpm]

Loctite do a thread sealant , I think its 577 or something like that , @Shaun will be along to confirm

Only for metal on metal joints mind you as in the case here.

 

[ShaunCorbs]

Dirty threads / old loctite 55

New clean threads loctite 577

Haven’t failed yet carry both

 

[Sharp Point]

I’ve bought my first bottle of 577 on Friday to make up 22 cast iron radiators and new valves, was a dream to make up. Today I noticed it’s still tacky... is this the norm, doesn’t it set?

 

[ShaunCorbs]

I’ve bought my first bottle of 577 on Friday to make up 22 cast iron radiators and new valves, was a dream to make up. Today I noticed it’s still tacky... is this the norm, doesn’t it set?

Yes you can wipe this off will go hard eventually but not needed

 

[Sharp Point]

Yes you can wipe this off will go hard eventually but not needed

What do you use to clean it off mr C?

 

[ShaunCorbs]

What do you use to clean it off mr C?

Blue roll, bounty, finger etc
Big wipes help if you’ve let it dry on something eg not noticed it

 

[Sharp Point]

Blue roll, bounty, finger etc

Cool, I didn’t know if it was a solvent remover
Bounty! I wouldn’t want coconut n chocolate everywhere

 

[OffshoreGas]

Most (all?) plumbing stuff is parallel thread. Parallel threads aren’t desinged to seal with PTFE, sometimes you’ll get away with it but locative is the right stuff for the job.

577 is pretty common/universal but it’s worth checking their website and your application.

They also do various activators that cut the curing time down massively. Without you’ve often got to wait hours to fill/test.

 

[rpm]

Other than compression fittings I disagree.

 

[OffshoreGas]

Other than compression fittings I disagree.

With which bit? Pointless extra words added for rule

 

[oz-plumber]

Have you 'Roughed up' the male thread?

 

[centralheatking]

With PTFE I was always taught to wrap it against the thread so it tightens up AND to twist it, ie rope it then carry on flat. All the above
is fascinating I am learning all the time thanks all above
centralheatking

 

[OffshoreGas]

With PTFE I was always taught to wrap it against the thread so it tightens up AND to twist it, ie rope it then carry on flat. All the above
is fascinating I am learning all the time thanks all above
centralheatking

PTFE tape not working with parallel threads is pretty much week day one/week one of any pipe fitting course, your taught some sort of thread sealant or a washer is always required.

Always seem strange its normal practice with plumbing an heating to uses tape. Obviously with the exception of tap connectors and similar using washers.

 

[quality]

577 will fix your issue as long as the fittings are sound

 

[Chalked]

I’ve bought my first bottle of 577 on Friday to make up 22 cast iron radiators and new valves, was a dream to make up. Today I noticed it’s still tacky... is this the norm, doesn’t it set?

It cures with lack of oxygen.otherwise it would set in the tube.

 

[Sharp Point]

It cures with lack of oxygen.otherwise it would set in the tube.

Everyday’s a school day !

 

[OffshoreGas]

Everyday’s a school day !

Google anaerobic thread sealants, loads of products to suit different materials/mediums/cure times.

 

[Chalked]

With the 577. Don’t use it on plastic threads! It makes the plastic brittle.
Only works on metal to metal.

 

[Warmiger]

If I have run out of the loctite mentioned.
I do use ptfe tape but I also smear jet blue on the outer wrap of the tape. I also apply it to the female thread. Obviously don’t allow it to go into the tap cartridges. I’ve never had a leak doing it this way either. This has saved me time and money and got me through.

 

[Pete321]

Just to follow up on my original post.

I decided to go with the Loctite 55 first, after watching the installation video and because I could get hold of it quickly. That sorted it out - a big relief, I can tell you

Thank you all so much for the great advice