ptfe on olives?

[fred]

Anyone wrap olives in ptfe ?

[Harry Bloomfield, Esq.]

fred pretended :

No, I might smear a bit of Plumbers Mait around it if I have doubts.

[Andrew]

I prefer mine with a dash of salt and few other veggies. Easier to digest

[Tricky Dicky]

+1

You can get sealing compounds for potable water too if it is a slight weep that is causing a problem.

Richard

[John Rumm]

Not as a general rule...

[Brian Gaff (Sofa]

Olives what? Sounds like a fetish I'd not heard of, who is Olive? Brian

[newshound]

I've only just figured out what you meant.

The standard advice is that you should not, presumably on the principle that any foreign matter across the sealing face could prevent the formation of a good seal.

While that might (or might not) be true of, say, hemp, I don't believe it would be an issue for PTFE because of its very low "flow pressure".

That said, personally I avoid putting it over an olive but I *do* use it on the male threaded portion, because the low friction means you get more "pinch" for a given torque.

It does not, in general, provide sealing even with multiple layers of tape on the threads because there is still likely to be a leak path back along the pipe. Although for tap connectors, lengths of tape twisted into a rope and wound round the pipe as a sort of backup to the fibre washer will sometimes provide a seal, especially for DHW where the pressure is lower than the cold main.

[Dave Plowman (News]

Yes. When I'm forced to use a compression fitting.

It does no harm and not as messy as a paste.

[Jimmy Stewart ...]

without fail

[Fredxx]

No, it shouts of amateur. I prefer to use any other lubricant if it is necessary. Petroleum jelly if potable.

PTFE should be confined to threads IMHO.

[Dave Plowman (News]

Oddly, it was a pro I got the tip from. Long before newsnet.

It's not acting as a lubricant. More of a sealer.

The threads pay no part in sealing a compression fitting.

[Fredxx]

You've contradicted this statement below?

I meant threaded fittings and not compression fittings, such as taper threads etc.

[The Natural Philosopher]

NEVER!

[Dave Plowman (News]

The question was about PTFE on an olive? Using it there helps the seal between the ends of the threaded part that the olive bears on. It might reduce friction too - but then I always tighten compression fittings till they groan. ;-)

[John Rumm]

One of the times that ptfe on the thread of a compression fitting helps

- you are able to work much quieter without all the squeaking and groaning :-)

(also good for restricted spaces which need short spanners, you can get better tightening)

[fred]

So we are all agreed on this then ? I had not heard of it until recently. We use a pressure pump and water tank to move water around the garden. The pressure tank seal failed so the whole caboodle had to be removed from its little house behind the garage, which involved breaking all the various connections. A real PITA and given that access is restricted once it had been reinstalled I was concerned to ensure all connections were water tight (plumbing is not my forte) so googled which was better ptfe or Boss White plus hemp and came across a discussion about ptfe and olives. Anyway I tried it on a few connections and all connections were perfect when reinstalled. I think after reading this thread I will wrap olives in ptfe in future as a belt and braces answer. Thanks to all who responded

[Roger Hayter]

The next question is whether to wrap some PTFE tape round the pipe *under* the olive. This could theoretically help the olive to seal to slightly scratched or deformed pipe.

When I first used compression joints I discovered an indirect disadvantage of using PTFE tape. It is possible to get a good watertight seal without tightening the fitting to the point that the pipe is deformed by the olive. The practical disadvantage of doing this is that the pipe can then pull out of the fitting, even just with water pressure if both pipes are not mechanically fixed elsewhere. This is a bad thing. A quarter turn after the nut is tight to stop the fitting coming apart is vital. The advantage of tape is only seen if pipe damage means this on its own would not be enough to prevent leaks.

[Dave Plowman (News]

Wrapping the olive with PTFE will do no harm. IMHO it gives a better chance of a good seal too. And unlike any other sealer gunge doesn't go off in storage. Or make a mess of your hands, etc. And is very cheap.

Hemp and boss white was never used on any compression fitting I've ever seen. More for a plain treaded connection, where the thread is the seal.

[Andy Burns]

I don't routinely use any gunge on compression fittings, but have used LS-X on problem ones (both copper and plastic waste) to good effect, it has a very long shelf life.

[Dave Plowman (News]

Good luck with that. The olive should already be a tight fit to the tube.