Odd Size Blanking Plug Needed

[Deleted member 18243]

A friend has an outside tap which is fed from the water supply of a disused outbuilding. The water main rises through the floor of this outbuilding to a stopcock about 18” off the ground. After the stopcock is a four-way junction piece; one outlet of this goes through the wall to the outside tap, one outlet has a small brass tap connected to it, and the fourth output is stopped off with a hex-headed blanking plug. The problem is that the small brass tap does not turn off fully, and so my friend has to keep the stopcock turned off, except when he wants to use the outside tap. When using the outside tap he has to place a bucket under the dripping inside tap and keep emptying it every few minutes!

He does not need the inside tap, and so I removed it to fit a blanking nut. However, the resulting hole has an 8mm thread, and I cannot find an 8mm blanking plug. Admittedly I’ve only looked in B&Q and Wickes, but whilst looking there I noticed that they do not stock many 8mm parts at all.

Does anyone know where I can get an 8mm blanking plug / nut? It would need to have a large flange area around the opening, as the body of the junction piece is about 1” diameter.

 

[breezer]

plumbers merchant?

 

[Deleted member 18243]

plumbers merchant?

Yes of course why didn't I think of that!

I didn't word my question correctly, sorry. What I want to know is - besides where can I get the thing from - is such a thing available, and am I doing the right thing or is there a better way I can solve this problem. (I'm not a plumber!)

 

[breezer]

I am not a plumber either, but i do find thenm to be very helpful if you explain what you want to do

 

[doitall]

Yep you can buy brass plugs that will fit, it wont be 8mm though.
Sounds like 1/8th BSP, but best to take the tap with you.

 

[chrishutt]

Why do you call it an 8mm thread? What dimension are you measuring? It's almost certainly one of the BSPT threads, namely ¼", 3/8", ½", etc.

 

[Deleted member 18243]

Why do you call it an 8mm thread? What dimension are you measuring? It's almost certainly one of the BSPT threads, namely ¼", 3/8", ½", etc.

I call it an 8mm thread because I bought something from B&Q called a 8mm compression stop end, discarded the nut and olive, and was left with a short hex-headed plug. This fitted into the threaded hole where the tap came from.

It could well be 3/8", I don't know, this is why I'm seeking advice. In any case, the B&Q thing did not work, as its head was to small to get a washer underneath.

I'd be glad of any help you can give, thanks.

 

[chrishutt]

8mm compression would probably be ¼" BSPT. What is the diameter of the plug including the threads? ¼" should be around 13mm (just about right to fit inside a piece of 15mm copper tube?).

 

[Deleted member 18243]

8mm compression would probably be ¼" BSPT. What is the diameter of the plug including the threads? ¼" should be around 13mm (just about right to fit inside a piece of 15mm copper tube?).

I measured the diameter of the threaded section and it's 13mm, or 1/2".

The hex head is 14mm across flats. It is the hex head that is the problem, it needs to be about 1" to give an effective sealing area. Thanks.

 

[Deleted member 18243]

8mm compression would probably be ¼" BSPT. What is the diameter of the plug including the threads? ¼" should be around 13mm (just about right to fit inside a piece of 15mm copper tube?).

I now realise why the item I bought is called 8mm - the plug is hollowed out to 8mm to fit over 8mm copper tubing, and is used with a nut and olive to form a stop end. It is completely the wrong item for what I need.

It looks like I need a 1/2" male threaded blanking plug, with a hex head of about 1" - nothing to do with compression.

 

[chrishutt]

¼" should be around 13mm.

I measured the diameter of the threaded section and it's 13mm.

So? Read my quote - it's ¼" BSPT!

 

[doitall]

Why not just take the tap in the shop and stop guessing

 

[Softus]

Why not just remove the four way junction piece?

 

[Deleted member 18243]

Why not just take the tap in the shop and stop guessing

I can't get to a plumber's merchant as they open only during work hours, and I work full-time.

 

[Deleted member 18243]

Why not just remove the four way junction piece?

It is soldered (I think - but it's hard to tell for all the corrosion and mess around it) and I don't have soldering equipment.