Plumbing: Teflon Tape and Threaded Joints

[buad hai]

Unfortunately, I have a lot of experience with plumbing; both original installations and repairs. I usually use Teflon tape on threaded joints. The usual recommendation (in the US, anyway) is to wrap the male thread two or three times. This usually works.

However, I've noticed that threaded fittings sold in Thailand seem to be made with rather less precision. Sometimes I need 10, 12, 20, 30 wraps before I can get a snug fit without cranking the threads all the way.

This was driven home to me today. I bought four hose nipples because our builder has yet to install them and I'd like to be able to turn the water to the house on as it's been connected since yesterday. I also bought two rolls of Teflon tape.

Just as I was about to do the work the plumber showed up and indicated he'd rather do it himself.

He ended up using one and a half rolls of tape for those four joints.

Granted, using all that tape prevents leaks, but it also reduces the friction in the joint enough that it is less secure than it would have been with more precise threading and much less tape.

Anyone found a better solution to the problem. (Aside from glue, I mean.)

[Thetyim]

There are many hydraulic sealants which will do the trick
I only one I have used is LocTite thread sealer with Teflon

Never seen it in Thailand though

[buad hai]

Never seen it in Thailand though

And therein lies the rub....

[Thetyim]

Well that didn't take long to find
Yes LocTite is available in Thailand and it is good stuff

wangdex

[buad hai]

It is good stuff. I'll try to find it. Home Pro maybe?

[Airportwo]

Be careful with the "steel" fittings that are available, especially the chrome ones made in Italy (thats what it says?) they are crap, after about a year I had quite a few literally disintegrate, they were a nightmare to get out!
use brass or stainless if you can find them.
I also used "liquid teflon' but bought it in Singapore, at the time not available here as - relatively - quite expensive.
Happy plumbing!
Cheers

[blackgang]

Here in lies the problem.
Threads need to be tapered on pipe so that the threads bind and seal before the bottom is reached, Teflon tape is a hyd sealant alright but just to fill small voids in the threaded material to prevent seepage, not to increase the diameter of the threads, or take any pressure of it's own.
Threads in Thailand are MACHINE threads, not NPT threads so they are straight and not tapered so they must bottom to seal.
Teflon tape or paste only fills the voids and as such will stand pressure but when used to increase diameter there is no strength of the sealant material and very much water pressure will blow it out and leaks will develope.
The only way that machine threads will seal is if a gasket, preferable an "O" ring is fitted and to hold, that will have to be in a special groove in the upper end of the threaded fitting above the threads, it does not work here and always tears when coming tight because the fittings were not designed that way.
Lock-tite comes in 2 different use types, Hyd sealant and thread lock,, is a very good sealant but not made for these applications, good on hyd. because it seals the same as tape and only seals the pores of the fitting, and if used on machine threads it is designed to actually weld the threads together to stop them from becoming loose from vibrations and has to be heated to get the threads to turn to disassemble any parts, works well on Motorcy assembly because of the alum and severe vibrations keep making things leak of fall off.
The only way I have found to put in plumbing is to use epoxy filler on the male threads of threaded fittings and wait til it has cooked off before turning on any pressure, that goes for both metal and plastic material.

[buad hai]

The only way I have found to put in plumbing is to use epoxy filler on the male threads of threaded fittings and wait til it has cooked off before turning on any pressure, that goes for both metal and plastic material.

In other words, you turn a threaded joint into a glued one?

[Ivor Biggun]

Put silicone sealant on the thread before joining and allow for it to set before turning on the water. Once set the joint can still be taken apart at a later stage.
In the UK they use a compound called Plumbers Mate which is none setting and is made precisely for your particular problem. I don't know if it's obtainable here but I guarentee it'll work if you find some.

[buad hai]

Is "Plumbers Mate" the same thing as ordinary pipe joint compound? The stuff we used before teflon tape came out?

[Airportwo]

Horse hair & liquid Teflon - seal anything!

[blackgang]

Yes basically it is glued joints. I have put in water filters, check valves and ball valves and it is terrible to have to use what ever means that you can to make something work.
The Thai ball shut off valves go to shit and freeze up in less than a year, and even the sink valves [faucets] go to hell in a short while too, and can get no repair kits.

I have tried silicone and it will work but if the pressure gets to high then it will blow out the same as a bunch of tape.

the none setting sounds like regular pipe dope.
I have done a lot of piping and I sure hate to do any here as it can never be done correctly with what you can buy to work with.

I have worked on things that had from 3,000 to 10,000 pounds of pressure on the lines and have never had so much trouble.

[Gerbil]

I have worked on things that had from 3,000 to 10,000 pounds of pressure on the lines and have never had so much trouble.

Fcuk me! That's one hell of a bum squirter you must have.

[Ivor Biggun]

Is "Plumbers Mate" the same thing as ordinary pipe joint compound? The stuff we used before teflon tape came out?

I think so. The original stuff used to set rock hard but Plumbers Mate is like putty but never sets.

[blackgang]

Have about 40# here at the house, but on large Hyd. equipment the pressures are sometimes quite high, never under 3K unless it is charge pressure then it will still be over 3k at times. High pressure steam will also run up to 1000 PSI at the bulkhead stops and at the turbines with temps in that same range, liguid water at over 300 deg. F. so you can't have to many leaks as when that stuff gets loose it can cut you in half and you can't see it.
And a leak in high pressuer hyd, will blow a hole thru you before you know about it.
Seen a guy one time let a Cooper Bessemer injector pop in the palm of his hand and he had a hole about the size of a 10 baht coin thru his hand.

[The_Dude]

Things to bring from the States. Let's see: Threader for sch 40 pipe with multiple heads ie., 1/2", 3/4", 1", Thread cutting oil, Pipe fittings, assortment of valves (ball, gate, hose bibe, check, etc.) liquid teflon , stainless, gas, water teflon tape. My guess also bring pvc primer and glue, ABS glue never saw the pipe in LOS but you never know. Bath and kitchen fixtures. Oh yeah decent Electrical fittings becouse the Thai ones suck!

[The_Dude]

Question- Does LOS have teflon tape for stainless and gas connections?

[buad hai]

Things to bring from the States

Stainless steel screws, galvanized nails, brass cup hooks, joist hangers....

The list goes on and on....

[jaiyenyen]

"Plumbers Mate" is a semi-sticky putty, mainly used for fitting brassware to sanitaryware, it never sets hard so taps etc are easier to replace. We also used it sometimes on the joint between wc pan and soil pipe.
The traditional way to seal a thread was Boss White and Hemp.
The hemp came in a big bundle like a blond wig, and Boss White in a tin.
Boss White is no longer used on drinking water in the UK, it is though to cause cancer, but there are now many other jointing compounds on the market.
Just before I left the UK, I was using a jointing string made Loctite, I think it was called Loctite 55, that was very good.

Regards
Jaiyenyen

[blackgang]

Question- Does LOS have teflon tape for stainless and gas connections?

I have seen the yellow stuff, but I have never seen it for sale, but it does appear to be here alright.

[Dalton]

Horse hair & liquid Teflon - seal anything!

Not oil and gas, unless you use special liquid, for those two.

[MC Pioneer]

"The traditional way to seal a thread was Boss White and Hemp.
The hemp came in a big bundle like a blond wig, and Boss White in a tin.
Boss White is no longer used on drinking water in the UK, it is though to cause cancer, but there are now many other jointing compounds on the market.

Can you remmeber Boss Blue? Then there was Boss Green wank stuff
Boss white is still used for gas fittings, I never used it on water fittings.
T Plus Two is what we used on water fittings a few years back not sure now though.

[jaiyenyen]

Yes, I remember all of those Finally ended up using something called Jet Blue which was suitable for everything. BTW I still love the smell of Boss White, it's a smell that brings back some happy memories. What a sad old git I am.

[MC Pioneer]

Yes, I remember all of those Finally ended up using something called Jet Blue which was suitable for everything. BTW I still love the smell of Boss White, it's a smell that brings back some happy memories. What a sad old git I am.

Yes jet blue didn't use it cant remember why.
the smell of boss white on your fingers
the flux we used cant remember the name but funk it stung if you got it in a cut

[jaiyenyen]

I used to use Everflux, it was a bastard when you got it in a cut.