Pipe thread sealant.

[phetphet]

I  have had to replace a couple of stop valves under the bathroom sink. Badly installed, the valves go into a female to male straight connector because the pipes are  buried about an inch and a half deep. Trouble is the joints keep leaking. All I can find in the stores is PTFE tape which is next to useless. I need some sort of thread paste.

 

Looked in HomePro,  Fahthaweeporn, and  the other place just before Maenam, (Home Depot?), but could not see  anything like what I need.

 

Years ago working back in the UK I used to use  a product called Stag along with hemp twine. Has anyone seen anything like  this here on Samui? Or recommend another product I might  be able to use?

 

TIA

[impulse]

A little spendy, but...

 

https://www.lazada.co.th/products/permatex-thread-sealant-with-ptfe-14a-1-i250667204-s386678424.html

 

https://www.lazada.co.th/products/577-loctite-no577-medium-strength-thread-sealant-i730470098-s1398228260.html

 

https://www.lazada.co.th/products/permatex-thread-sealant-with-ptfe-14d-16-473-ml-i737700898-s1409566178.html

 

https://www.lazada.co.th/products/permatex-pipe-joint-compound-16-oz473ml-i731080932-s1409430422.html

 

https://www.lazada.co.th/products/permatex-51h-118-ml-i688243000-s1323712896.html

 

And I just looked through the first few of many pages brought up by a search for thread sealant.  One of 'em is bound to work for your application.

 

Edited December 9, 2020 by impulse

[NanLaew]

1 hour ago, phetphet said:

...a female to male straight connector...

 

This is called a pipe nipple. You haven't specified where the leak occurs: at the outer end where the flexible hose to the taps connect, or the inner end buried in the wall. I would suspect any leak is due to lack of effort in making them tight? This may be due to difficult access or lack of proper tools.

 

Are the threads in the buried female pipe ends brass or blue plastic? If brass, I would suggest trying longer nipples so that after the thread tape is applied, they can be tightened into the female connection with a larger-jawed pipe wrench. If the buried female pipe ends are blue pvc pipe, chances are they will be stressed already hence the leaking. In that instance, the commercial pipe sealant you need will be required. If using braided or flexible hose, check the seating of the rubber sealing washer. Ideally, these do not need thread tape and I have see these weeping when thread tape is mistakenly used. The rubber washer should be all that's needed but if the metal 'seat' is rough or corroded, a light application of tape may suffice.

Edited December 9, 2020 by NanLaew

[Andrew Dwyer]

White pipe sealant from Loctite is available from Lazada, there are a few variants ( high temp, high pressure, with Teflon, etc ) so take care but generally the numbers starting with a 5 ( 567, 572, 577, etc ) are pipe sealants. Not to be confused with “thread lockers” which are generally a blue or red colour.

If there is a SCG stockist near you check them out , I found some at a Homemart store ( but nowhere near your location ).

 

It is quite pricey !!, but designed for the job .

 

A mishmash of different/cheap pipe fittings are commonly used here and the usual solution is to use half a roll of PTFE tape on each joint .

[phetphet]

10 hours ago, impulse said:

A little spendy, but...

 

https://www.lazada.co.th/products/permatex-thread-sealant-with-ptfe-14a-1-i250667204-s386678424.html

 

https://www.lazada.co.th/products/577-loctite-no577-medium-strength-thread-sealant-i730470098-s1398228260.html

 

https://www.lazada.co.th/products/permatex-thread-sealant-with-ptfe-14d-16-473-ml-i737700898-s1409566178.html

 

https://www.lazada.co.th/products/permatex-pipe-joint-compound-16-oz473ml-i731080932-s1409430422.html

 

https://www.lazada.co.th/products/permatex-51h-118-ml-i688243000-s1323712896.html

 

And I just looked through the first few of many pages brought up by a search for thread sealant.  One of 'em is bound to work for your application.

 

Thanks. Didn't even think of Lazada. I really need it now as everything shut off at the moment, and guy coming to build new under sink cabinets tomorrow. Old ones destroyed by leak. .  But will order today anyway.

[phetphet]

10 hours ago, NanLaew said:

 

This is called a pipe nipple. You haven't specified where the leak occurs: at the outer end where the flexible hose to the taps connect, or the inner end buried in the wall. I would suspect any leak is due to lack of effort in making them tight? This may be due to difficult access or lack of proper tools.

 

Are the threads in the buried female pipe ends brass or blue plastic? If brass, I would suggest trying longer nipples so that after the thread tape is applied, they can be tightened into the female connection with a larger-jawed pipe wrench. If the buried female pipe ends are blue pvc pipe, chances are they will be stressed already hence the leaking. In that instance, the commercial pipe sealant you need will be required. If using braided or flexible hose, check the seating of the rubber sealing washer. Ideally, these do not need thread tape and I have see these weeping when thread tape is mistakenly used. The rubber washer should be all that's needed but if the metal 'seat' is rough or corroded, a light application of tape may suffice.

The pipe is the blue plastic stuff coming up inside the wall with a brass elbow on the top. Can't find any longer brass nipples, and I have tightened up as much as I dare.Scared of breaking the plastic pipe.

I tightened the stop valve right into the nipple as far as it would go, before screwing  the whole assemble into the elbow in the wall.

The problem is a lot of the Thai nipples  are straight threads, not tapered. As suggested by other posters, going to try Lazada for pipe thread paste. I don't want Loctite, or anything that is going to lock the thread permanently. Stag B would be ideal, or something similar. Now where to find a hank of hemp?

Edited December 10, 2020 by phetphet

[petermik]

7 hours ago, phetphet said:

The pipe is the blue plastic stuff coming up inside the wall with a brass elbow on the top. Can't find any longer brass nipples, and I have tightened up as much as I dare.Scared of breaking the plastic pipe.

I tightened the stop valve right into the nipple as far as it would go, before screwing  the whole assemble into the elbow in the wall.

The problem is a lot of the Thai nipples  are straight threads, not tapered. As suggested by other posters, going to try Lazada for pipe thread paste. Now where to find a hank of hemp?

Sounds as if the brass elbow is split...tape will not work,go for one of the joint sealers on Lazada that has been mentioned earlier....