Of Taps and Tails

Got new tap, swivel-spout mixer, with the usual metal mesh outer. Now, a couple of things:

how durable are these tails? Pressure is about 4 Bar, so quite a force on the hose.

the tails have 10mm thread into the tap, with a little O-ring as a seal. If I tighten a tail as much as I can I can still unscrew it by just twisting the other end. The hex on the tail is no good as it's deep within the base of the tap.

As the water supply is in Speedfit and tails end in 15mm female I'm getting a pair of Hep2O push-fit tails.

Spawn of the devil IMHO, horrible things in almost every way, I've yet to have a good experience with them and they're virtually standard now.

I often use a locking sealant (Rocol I think, like a form of Loctite) for such things but it depends on how the thing is sealed in the first place. Like, if it uses an 'O ring' then it could be tricky, should the seal relax in time and the nut need tightening (although the lock / sealant I use it 'soft hold').

If it could be sealed via the nut without the washer (eg, it's not a swiveling nut) then you could use the thread locker / sealant and not worry about relying on the washer.

I would especially do all this if you could still get the tap out with the tails on (so you could work on them out of the sink).

I also use it on all my pneumatic / air-line fittings as it allows you to rotate things into the right position (water traps and the like) without having to f about with PTFE tape (it sets very quickly).

Cheers, T i m

/The O Ring is the seal - the thread is merely holding stuff together.

Not if the seal is (effectively) moved to the thread (and my point).

eg, I would rather have the end of the tail sealed on where it couldn't accidentally unscrew / leak over time than relying on a rubber washer and the friction of the compressing nut on the thread that might.

Assuming the nut isn't a swivel type, a potable fast setting / soft hold sealant does all that is required and with less risk? Cheers, T i m

The braid on the rubber hose looks to be stainless steel. In my case it wasn't, it has started to rust. These flexibles are best avoided IMV

While excellent for doing up the retaining nut, they are not much use for the hot and cold flexi tails, which is what I get the impression the OP is talking about.

Thanks, but the crimp part is bigger than the flats on the hex bit.

I have not had any problem with them in general. Just make sure you don't kink the hoses when tightening.

Firstly, its much easier to get these well fixed before you mount the tap in place - then you can use the hex ends with a spanner.

You will need the box spanners however (linked by Andy earlier), for doing up the crescent washer and gasket that fixes the tap to the basin since you now need to reach into the narrow space between the tail ends.

Yup that looks fine. Don't forget to include a service valve in there somewhere.

I normally use the supplied flexi tails with their 1/2" BSP female end, and screw that directly onto the free end of a full boor half inch compression service valve (having removed the nut an olive).

Like in the photo here:

Not required - the O ring makes the seal. I sometimes assemble with a smear if silicone grease on the O ring.

Not much chance of using a sealant on the 10mm thread - deep in the tap and seem to have silicone grease on them. Even the 15mm nuts won't pass through the threaded collar that holds the tap i (with nut and seals, of course); the push-fit connectors are bigger.

I agree - if I'm not happy with them I'll se if I can get some copper ones.

My mixer had some rigid 'stalks' that screw into the block, then you can use compression (flexi or not) onto those.

Correct - also if I tighten a tail as much as I dare it is still easy to undo - doesn't seem to be at all secure.

Are they shortish 'stalks' or copper tails like these?

As I said, the crimp on the tail is bigger than the hex so no go there.

The valves are at the bottom of the feeds so that I can make mods. higher up if necessary. Just tried on an old service valve and it is, of course, OK. Rather bizzarely the 15mm ends of the tails are for a face seal - like the top of 'conventional' tails, so no good for compression fitting. I think that the Hep2O is the simplest way but I'll get some straight comp. connectors and they should be useable between the 2 face seals.

Some comments on SF's site say that the provided seals are crap. I noticed that the new basin isn't as well formed around the outlet as is the >30 yo one. Also, the measurement given is 70mm but the outlet isn't flat-bottomed and 70 looks as if tightening wil deform the flange; 60 might be better.

Compression fittings aren't designed to mate directly to a rubber washer as the pointed edge can cut into (through) the washer.

Adaptors are available that provide a flat mating face:

Note that the instructions for our our monoblock tap (a Franke) says to only hand-tighten the tails and explicitly says not to use any tools. It is designed so the o-rings seal against the side walls - not under compression with a mating face (it's not a washer) - and would remain doing so even if undone several turns which wouldn't happen given the compression end anchors the flexi in place. Might yours be the same?

Like those AFAIR, not had to look at them in the 12 years since installed, thankfully.