3/4" bib taps

[Fred]

Hi,

I bought a 3/4" bib tap from Tool station. I was hoping to find a connector to screw onto the spout onto which I could fit Hozelock (or similar) fittings.

The problem I have found with bib taps is that they are referred to as either 1/2" or 3/4" taps but they have two threads: one on the spout and one on the back of the tap. The tap manufacturers refer to the measurement of the thread on the back of the tap.

A 1/2" tap has a 1/2" thread on the back of it but it has a 3/4" thread on the spout. A 3/4" tap has a 3/4" thread on the back and something else all together on the spout. I think the fact that both sizes of taps have a 3/4" thread somewhere is what is responsible for all the confusion. I have tried a number of people and no-one has been able to supply the right part!

The consensus is that a 3/4" tap has a 7/8" thread on the spout but I can only find 3/4" and 1" hose adaptors. Hozelock do sell a 22mm adaptor but "not for use in Britain".

7/8" is roughly 22mm, so I am wondering whether your 22mm adaptor would fit; is it a BSP thread or something completely different? It is intended for the European market; do they use a metric thread instead?

The tap came with a ribbed brass fitting that the hose pushes over. I guess I should stop being so fussy and stick with that! The problem is it isn't as easy as a quick release fitting when you want to remove the hose when you have finished to keep the garden looking tidy.

Has anyone found a 7/8" adaptor anywhere?

TIA

[cynic]

Is there some reason why you insist on a 3/4" tap to feed a garden hose with? What size hose do you use with it?

[Bob Minchin]

7/8 BSP is the thread that would be cut on some 7/8 bore iron pipe years ago (if such stuff ever existed). It will be much greater diameter over the thread than 7/8" so your comparison with 22mm is not relevant.

Why not fit a short stub of hose on and then put a your chosen quick release fitting on that?

Bob

[Baz]

If it measures 7/8" then it is 1/2" BSP.

1/8" BSP = 10.3 mm OD 1/4" BSP = 13.8 mm OD 3/8" BSP = 17.2 mm OD 1/2" BSP = 21.4 mm OD 3/4" BSP = 26.6 mm OD 1" BSP = 33.5 mm OD

Baz

[The Medway Handyman]

Having spent 25 odd years selling pressure washers, I've never come across a threaded tap that wasn't 3/4" BSP.

[Roger Mills]

I don't know about 3/4" taps, but 1/2" taps *usually* have a 3/4"BSP thread for the hose connection. It's not universal though - I've had them with

5/8"BSP threads, and have even seen them with 1/2"BSP. Some Hozelock-type fittings come with reducers to enable them to fit taps of any of the 3 sizes which I have mentioned.

[Fred]

It is on the water butt rather than mains water; I thought the larger bore would help counter any flow issues due to it not being at mains pressure.

[Fred]

That's looking like the only way, thanks.

[Fred]

As I understand it most are 1/2"BSP where they screw to the wall plate and 3/4" BSP for the hose connection. I bought this larger one which is 3/4" at the wall plate and 7/8" for the hose because it is fitted to a water butt and I wasn't sure how good flow would be from a gravity source. I'm thinking I might fit a "normal" bib tap to see whether there is any difference and if not I will be able to use the connectors commonly available.