Compression Blanking Nuts

[imroberts]

I'm in the process of fitting a new bathroom and need to blank off the end of a couple of compression elbows temporarily (potentially a few weeks).

I'd planned to fit a short length of copper pipe with a stop end, however I see that compression blank nuts can be bought which I assume will just screw onto the end of the elbow and seal with a rubber washer.

However, I notice that Screwfix sell two variants, one of which is advertised as 15mm and the other as 1/2"

https://www.screwfix.com/p/51939

https://www.screwfix.com/p/55441

I always understood that the thread on a 15mm compression fitting was 1/2" BSP but I'm assuming either I'm wrong, or these two products are the same thing?

 

[Stuckinarut]

They do look identical, however the compression blanking nut mentions reusable with a new olive, so I’d personally go with the 1/2” blank nut, it’s what I’ve used in the past.

 

[DP]

Or get these

https://www.screwfix.com/p/flomasta-brass-compression-blanking-disc-caps-15mm-2-pack/64472

Blank cap will fit a 15mm fitting and a 1/2” MI
The bevel in 15mm fitting may cut into the sealing washer in blank cap- blanking disc locates where the olive would fit.

 

[Mottie]

Can’t you just use the centre piece out of this?

 

[Madrab]

Can’t you just use the centre piece out of this?

Erm, not sure that male cap would fit onto a female threaded leg of an elbow?

@imroberts either or will do but as suggested, don't over tighten it, the fluted end on the elbow that takes the olive can cut into the seal in the blanking cap and then it'll leak. May be easier just to use a little stub of pipe and use a push fit stop end?

 

[Mottie]

Erm, not sure that male cap would fit onto a female threaded leg of an elbow?

Ah, right. I understand now. Dunno WTF I was thinking…..

 

[Madrab]

Ah, right. I understand now. Dunno WTF I was thinking…..

 

[Stuckinarut]

Ah, right. I understand now. Dunno WTF I was thinking…..

Instead of blanking the male part of the elbow removed the elbow so left with a nut and olive?

 

[Mottie]

Ah, right. I understand now. Dunno WTF I was thinking…..

I was just thinking of blanking an open pipe. Never mind.

 

[imroberts]

Or get these

https://www.screwfix.com/p/flomasta-brass-compression-blanking-disc-caps-15mm-2-pack/64472

Blank cap will fit a 15mm fitting and a 1/2” MI
The bevel in 15mm fitting may cut into the sealing washer in blank cap- blanking disc locates where the olive would fit.

I assume that would fit in the end of the elbow with the original nut?

 

[imroberts]

Can’t you just use the centre piece out of this?

View attachment 376494

This would work just as well actually - I have no need to leave the elbows in place as the whole lot will be replaced at a later date anyway.
I'd just assumed I would leave them in place and blank off the open ends.

Removing the elbows completely and fitting the centre of this on the end of the pipe I'm left with would probably be a better solution.

 

[Madrab]

I was just thinking of blanking an open pipe. Never mind.

Of course - that would work just as well

Guess none of it was clear at the time as the OP mentioned blanking the elbow - as if they were to be kept.

 

[DP]

I assume that would fit in the end of the elbow with the original nut?

Yes

 

[johnny2007]

I use hep2o caps.
Can be fitted in 1 second and removed without tools.