PTFE challenge!

[eyecatcher]

We have a leaking service valve for a bum gun at the spa.

I have traced it to the head of the tap but it will not tighten up.

 

So lets spend 65bt and have a new one.

The problem lies now with how to make the new valve watertight.

 

You see i need to fix the new valve onto a male thread but the male thread is back beyond the face of the wall tiles...two layers of tiles!

 

The space is insufficient to wrap ptfe so would it be futile or at worst stupid to smear the female part of the thread with silicone.

 

Any bright ideas?

[Crossy]

We got some splodge-it-on sealant which you could use on both male and female bits :)

 

OR

 

Get one of the brass female-female couplers, make sure it will tighten reasonably well through the tiles (knock a few bits foo the tiles if needed), then put a good splodge of epoxy on both threads, wind it on and go for a lot of beers. Result a new female thread slightly proud of the tiles.

 

 

[roo860]

We got some splodge-it-on sealant which you could use on both male and female bits :)
 
OR
 
Get one of the brass female-female couplers, make sure it will tighten reasonably well through the tiles (knock a few bits foo the tiles if needed), then put a good splodge of epoxy on both threads, wind it on and go for a lot of beers. Result a new female thread slightly proud of the tiles.
 
 

Sounds disgusting!!

Sent from my SM-G920F using Thaivisa Connect mobile app

[petermik]

7 hours ago, Crossy said:

We got some splodge-it-on sealant which you could use on both male and female bits :)

 

That,s interesting Crossy,might try that myself.....but I,ll have to check with the missus first to see if she is agreeable

[Crossy]

5 minutes ago, roo860 said:

Sounds disgusting!!

 

The best things often do

 

[petermik]

Here,s hoping the mods don,t shut this thread down..............

 

 

[Crossy]

Why would we do that, we are talking about doing it yourself?

 

Whatever "it" is :)

[Muhendis]

7 minutes ago, Crossy said:

We got some splodge-it-on sealant which you could use on both male and female bits :)

 

OR

 

Get one of the brass female-female couplers, make sure it will tighten reasonably well through the tiles (knock a few bits foo the tiles if needed), then put a good splodge of epoxy on both threads, wind it on and go for a lot of beers. Result a new female thread slightly proud of the tiles.

 

 

Go for Crossy's splodge or poxy stuff or you could get a bit of squirt on liquid nails construction adhesive which will stick to anything (almost) and will remain slightly flexible so allowing for temperature effects  on the different thermal expansion characteristics of whatever the materials might be. Then go have a beer or three.

[Crossy]

@Muhendis I've not had a lot of success with the construction adhesives in wet environments, they are not as waterproof as one would imagine.

[Muhendis]

1 minute ago, Crossy said:

@Muhendis I've not had a lot of success with the construction adhesives in wet environments, they are not as waterproof as one would imagine.

There's some stuff I've used which is a bit like Evostick and seems Ok for stopping water around screw joints.

[KittenKong]

15 minutes ago, Crossy said:

@Muhendis I've not had a lot of success with the construction adhesives in wet environments, they are not as waterproof as one would imagine.

 

Back in Europe I used a specific epoxy compound for underwater use with great success to repair a cracked cistern. Lasted for 20 years whilst I still owned the building and, for all I know, is still going strong.

 

The important thing was to let it cure (24 hours) before getting it wet or putting it under any pressure. I imagine that once cured it would be impossible to get the fixture off without ripping the whole thing out of the wall.

 

Never seen it here but then I've never looked for it.

[johng]

The epoxy is a good idea but it's a one shot deal you have to makes sure there is enough to seal the threads probably first time, if there is a still a leak after epoxying the threads (you have to let it cure before turning water on again) it will be a devil of a job to get the fixture off again normally a thread deeper inside the wall will undo or something will break !

[Crossy]

Yeah, epoxy is definitely one-shot, that's why I suggested using a coupler. Once set you can thread a new valve in with the PTFE and still get it off afterwards :)

 

A decent waterproof silicon would probably work as well and be more removable.

 

[KittenKong]

Hmm. Liquid PTFE: http://www.screwfix.com/p/flomasta-ptfe-liquid-50g/5321j

[eyecatcher]

50 minutes ago, roo860 said:

 

 

Sounds disgusting!!

Sent from my SM-G920F using Thaivisa Connect mobile app
 

 

 

yes but, there is beer involved apparently so I am liking this already

[eyecatcher]

4 minutes ago, KittenKong said:

Hmm. Liquid PTFE: http://www.screwfix.com/p/flomasta-ptfe-liquid-50g/5321j

sounds like Tippex correction fluid!

[KittenKong]

Just now, eyecatcher said:

sounds like Tippex correction fluid!

 

Hopefully a bit more robust than that! The reviews seem to be pretty favourable and it seems well suited for this job.

[eyecatcher]

12 minutes ago, Crossy said:

Yeah, epoxy is definitely one-shot, that's why I suggested using a coupler. Once set you can thread a new valve in with the PTFE and still get it off afterwards :)

 

A decent waterproof silicon would probably work as well and be more removable.

 

Yes that was my concern about applying silicone directly to the thread...50/50 it will work or it will not

 

a coupler is an idea but same result.....maybe this is where the beers comes in

and then I still have a new tap(photo) to change again.

 

I am still wondering how to get PTFE on the thread and may just try wrapping a load around a choptstick and then running the chopstick around the thread.

[eyecatcher]

48 minutes ago, petermik said:

Here,s hoping the mods don,t shut this thread down..............

 

 

screw 'em

[BaldPlumber]

Use jointing paste in the female thread.

[eyecatcher]

6 minutes ago, BaldPlumber said:

Use jointing paste in the female thread.

would I (English) understand that as  "plumbers mate"

[Artisi]

You have time as it takes this epoxy a little while to harden

3 hours ago, Crossy said:

We got some splodge-it-on sealant which you could use on both male and female bits :)

 

OR

 

Get one of the brass female-female couplers, make sure it will tighten reasonably well through the tiles (knock a few bits foo the tiles if needed), then put a good splodge of epoxy on both threads, wind it on and go for a lot of beers. Result a new female thread slightly proud of the tiles.

 

 

I would go a little further just to make sure, starting with a piece of wood (maybe a piece of dowel) or similar that would fit neatly into the bore of existing buried male thread, carefully fill the whole area within the wall cavity with epoxy.  I would look at the epoxy used to fix reinforcing bar into concrete as it is fairly firm when mixed and doesn't run everywhere  - wait awhile until it starts to firm up - careful attention needed here - retain the wooden dowel in place and enter the female / female coupler amply coated internally and externally with the same epoxy  (only at the end going into the wall) and screw it into place - then remove the dowel and clean up the internal thread at the outer end of the coupler -  tooth bush and water (damp only) should do the trick for you --  also ensure any void in the wall cavity / coupler is filled in - at the wall / coupler interface  smooth off any surplus epoxy - use water and your finger to give a perfectly smooth finish - take your time this epoxy is not all that fast curing -  but once it starts to cure that's it. Guaranteed to last this century  and probably the next.

[Artisi]

2 hours ago, eyecatcher said:

would I (English) understand that as  "plumbers mate"

I would say yes.

 

[luudee]

5 hours ago, KittenKong said:

Hmm. Liquid PTFE: http://www.screwfix.com/p/flomasta-ptfe-liquid-50g/5321j

 

 

Is liquid PTFE available in Thailand ?

 

Thanks !

rudi

[BaldPlumber]

would I (English) understand that as  "plumbers mate"

No, different product completely.

A proper sealant will work OK, used to make gas tight joints so it will certainly work on water ones.

About 50 baht or so in the DIY places.

Guaranteed to work.

If you're local to me, I'll do it for you.

[BaldPlumber]

BTW, PTFE, especially the gas, one wrap variety, is certainly better.

But, for an application where the orientation of the fittings is not important, then the sealant is perfectly good.

[KittenKong]

1 hour ago, luudee said:

Is liquid PTFE available in Thailand ?

 

I've never looked for it so I dont know.

[wayned]

I used a two part epoxy called AQUA SEAL bought it in Home Pro and still available, to "temporarily" fix a couple of leaks when I built my house 18 years ago having every intention of going back and fixing them properly later.  It's still there and not leaking and I have learned not to fix something that's not broken.

[leyali]

I would put a o-ring on the male thread in the wall and then screw the valve in till they press the o-ring. Or put a flat o-ring in the female thread and screw them in.