PTFE tape V boss/hawk white/plumb blue joint compound

[DIYedboy]

I've just installed a HW cylinder with 10 turns of PTFE on the cylinder tappings. One has started to drip, so I had to redo it. As I undid it, the PTFE had been squeezed down to nothingness, so I thought to myself 'I wonder if I'd used compound on the threads whether I would still have got the leak?

 

[glasgowgas]

did you put the ptfe on the right way??

 

[petit_pablo]

There never is much left on the thread if a fitting is unwound again, just a bit at the end of the threaded part.

I never normally have issues with using PTFE, can smear some compound as well if you like.

 

[DIYedboy]

I wound the tape onto the tapping in the same direction the coupler would be wound on. It just seems that compound has more 'guts' in it than PTFE or am I wrong?

 

[doitall]

Very wrong.

Compound on it's own is no good.

Buy a tube of Loctite 55 string, brilliant stuff for threaded joints.

 

[DIYedboy]

Loctite string...................good one, I'll get me some of that then.

DIA, you say compound on it's own is no good, so if I'd used just that on the cylinder tappings are you saying that they would have leaked?

Is there a rule about when compound should be used and when PTFE tape should be used?

I use compound in front of an olive on a compression fitting, but that's about it

 

[bathstyle]

PTFE tape seems a lot thinner than it used to be, give it a good 15 wraps and it should be fine, you will find that the vast majority of Plumbers never have a problem using PTFE, including myself.

 

[doitall]

Loctite string...................good one, I'll get me some of that then.

DIA, you say compound on it's own is no good, so if I'd used just that on the cylinder tappings are you saying that they would have leaked?

Is there a rule about when compound should be used and when PTFE tape should be used?

I use compound in front of an olive on a compression fitting, but that's about it

You can buy Lsx which does the job (maybe) only time og seen it used, it took the guys 3 attempts jointing compound is for olives and hemp, and you shouldn't need anything with Ptfe or Loctite 55 string.

 

[DIYedboy]

Great, thanks DIA n rest....................if you've got a thread it'll be 15 turns of PTFE or Loctite string, if you've got a tin of compound keep it to wipe on ya olives or mix with hemp if ya gonna do 'big jobs'

 

[doitall]

Don't use hemp on potable water though, it banned, but ok for heating etc.

 

[DIYedboy]

what's always puzzled me .................why is drinking water called 'potable'?

 

[kevplumb]

coz if yer in lancashire you have a "pot" of tea

put wud int ole lad an mash pot

 

[DIYedboy]

Eeeeee by t'heck Kev arl'll go t' foot of our stairs......... by 'eck as like bonny lad that's a gud 'un

 

[kevplumb]

 

[WDIK]

what's always puzzled me .................why is drinking water called 'potable'?

adj.
Fit to drink.

n.
A beverage, especially an alcoholic beverage: wine and other potables.

[Middle English, from Old French, from Late Latin pōtābilis, from Latin pōtāre, to drink, from pōtus, a drink.]