BSP pipe fitting fitting

Could you fit one or more large rubber tap washers (perhaps opened out to increase the bore) so that the end of the reducer presses against it/them? John

Wrap the thread with hemp and use jointing paste - works every time. If appropriate, use a fibre washer for the male to bottom onto.

If it needs a tapered thread, it'd never work with a parallel thread.

This is the filter:

While I can use a BSPP male, it would need to come with a washer on the end. I'm not seeing such things.

I think a BSPT male would fit, but according to this requires sealant:

Theo

Hmm, possibly. Although there's about 1" to be made up which is a big stack of washers...

Theo

At that size a taper thread will seal perfectly with 15 - 20 turns of thin PTFE tape. A parallel thread won't seal without some setting sealant, unless a fibre washer will fit *over* the male thread and the adapter has a flat shoulder to meet the plastic round the female thread, but I wouldn't trust that solution.

If you can't find an adaptor, you could always do it in steps; convert from 3/4" BSP TM to compression first, then go from that to something you can mount your flexi on:

Both halves can (and should) be taper... that way they bind up as they tighten. You need a sealant like PTFE to make the final seal.

Jet V2 is non setting - it works as a lubricant, and helps make a final seal. You won't be able to use it at any thickness. So good for threads on compression joints (reduces squeaking, and requires less torque to tighten), also as a thin film on mating surfaces like cone joints on on olives where it will seal very slight imperfections on the surface.

There's no space for anything else, I need to take an immediate turn upward. There is barely enough space for the curve on the flexi as it is.

I haven't managed to find any 3/4" BSPT fittings locally. The reducers Alan mentioned plus an elbow might work, but I'd have to order them in. If I can find a 3/4" BSPT elbow then I have more space to adapt that to 1/2" BSPP.

I've now got some Fernox LS-X, which seems to be basically silicone in a tube. Is it worth trying to seal what I've got with that, or is it a waste of time and I'll need to get a BSPT thread?

Thanks Theo

Thanks. Today I had to do the same for some 1/2" and I used some of these:

Theo

As I said earlier, I would use a hemp wrap and jointing paste.

I wouldn't trust it permanently, though it would probably work at first.

You can certainly get an adapter 1/2" to 3/4" taper male, the only question is whether the flexi would fit far enough on the taper male 1/2" side. I suspect it would.

I agree that would work, but use potable water jointing paste! The traditional ones aren't. Don't know if hemp is approved.

And you could use an elbow to avoid a sharp bend in the flexi, although you're still stuck with a taper male thread.

I would be interested in the collective wisdom about whether a die nut could be used to convert a 1/2" male taper thread to parallel? Although you can get a standard die for about £4 if you have a suitable diestock.

I fall on my sword - I hadn't spotted that this was for a water filter. There are WRAS-approved pastes but hemp is not. A tapered fitting is probably the only viable WRAS-approved solution

LSX will probably work. As would "enough" ptfe (using string rather than the thin tape would probably work better). Hemp and V2 could also work.