110mm drainage pipe and strap a on boss or three...

[dobbslc]

I have a brown 110mm soil / drainage pipe under the floor and need to install three waste pipes into it. I've got three Flowplast strap on boss's and fitted one yesterday but on testing by blocking and filling the pipes with water it had a small leak around one side!
I've used these before with no trouble at all but I'm sure it wasn't on brown drainage pipe but grey soil pipe, is there any difference between the colours?

I bought new fresh solvent weld adhesive and cleaned the surfaces before I started, What's gone wrong?

 

[Welderpaul]

I have a brown 110mm soil / drainage pipe under the floor and need to install three waste pipes into it. I've got three Flowplast strap on boss's and fitted one yesterday but on testing by blocking and filling the pipes with water it had a small leak around one side!
I've used these before with no trouble at all but I'm sure it wasn't on brown drainage pipe but grey soil pipe, is there any difference between the colours?
View attachment 508291
I bought new fresh solvent weld adhesive and cleaned the surfaces before I started, What's gone wrong?

It's the wrong type of plastic for solvent welding onto. You'd need to cut a full bore tee into it then an adapter to pick up the waste pipe.

 

[sg66]

You have a strap on with not much flange, I know that sounds bad.....

You also have crap solvent glue, you should be able to bond it on but you need better glue, I've done it without leaks onto brown.

Options, get some good solvent weld, weld on 725, it's aggressive mind, clean up the area properly, use proper cleaner, rough it slightly.

You can solvent weld brown it's just not usually recommend because it's usually in the ground and inaccessible.

If you wanted to you could cut a section out, get a couple of slip joints, splice in a bit of grey and use that, but there is no need.

 

[dobbslc]

It's the wrong type of plastic for solvent welding onto. You'd need to cut a full bore tee into it then an adapter to pick up the waste pipe.

I've just had a search of this pipe from Screwfix and Toolstation where I probably bought it from and it's uPVC so should be ok with solvent weld adhesive.
Now I'm worried.

 

[Blobber]

You used to able to get a thicker solvent, gap filling in think it was called, much better for strapons

 

[Onoff]

Without thinking I ran a length of brown, underground pvc soil pipe internally whereas I should have used the black or grey stuff. I went through the same worries. I went from brown to solvent grey and different makes to boot so it was perhaps a tad "sloppy".

I roughed up the brown and brushed on the normal brush in a tin solvent but it didn't seem to really touch the brown. I think you need to "concentrate" the solvent in a tight fitting joint for it to work best anyway.

I used this stuff in the end on recommendation:

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Pipe & Fittings / Cement - PN: 18495 - Order Gas and Plumbing Supplies online at BES.co.uk. Low Prices, Free Next Day Delivery Available, 15k Plus Products in stock

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Then backed up the joint with the white stuff. Can't remember if it was CT1 or Sikaflex EBT.

https://flic.kr/p/WGmbq8

https://flic.kr/p/WLvfHQ

Been done 10 years. It would have smelt / I'd have seen it if it had leaked.

https://flic.kr/p/QUh6Gv

 

[Agroshield]

It's the wrong type of plastic for solvent welding onto.

I do not think soil pipe is like waste pipe, where the push fit is polypropylene. AFAIK, the only difference between solvent weld soil and push fit soil is the fittings, not the pipe material. The only difference between brown and grey/black soil is the grey/black has UV stabilisers in it for above ground use.

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Abrading the surface of the pipe might make a better bond. Do a dry fit and sand down any obvious high spots or moulding flash so there is a uniform gap. As there is plenty of space around the boss, perhaps make a ringpiece (3DP) to go around the boss and clamp it down while the glue sets.

 

[Onoff]

Cleaning the faces with acetone helps. Or foam gun cleaner, IPA etc.

 

[dobbslc]

I've got some acetone although I used alcohol on this one.