Everyone glues their ABS to PVC pipe - surely not?

[joidevie]

We're in middle of fitting a couple of 'receveurs a carreler' onto/into a new screed.

I'm looking around and it seems everyone simply 'glues' a manchon onto the bonde (made from ABS) and then carries on in PVC 40mm. It seems to go against all the wisdom in that you should not (cannot) glue (weld) ABS to PVC, yet all the videos/images online are showing people blissfully carrying on..

What should one be doing?

One added complication is that we brought our 'kit' from the UK and the 'out' from the waste is 56mm (OD) rather than a French 50mm (OD). Our helpful supplier in the UK is forwarding us an 'adapter' that pushfits onto the 56mm and supposedly leaves us a 40mm to 'glue' onto. It's not arrived yet, but I'm looking around frantically as to what to do.

A visit this morning to a good (not Bricodepot) Brico store revealed firstly suggested 'just glue a manchon onto the bonde' to another chap who acknowledged that ABS > PVC is not right, and he recommended a rubber/jubilee clip 'manchon multi-materiaux' diametres 38-48mm direct onto the bonde, then a PVC manchon or pipe.

This could work as I could 'stretch' the rubber fitting over the 56mm bonde and ditto the other end to a 50mm French PVC, but as it's all going to be tiled over, alarm bells are ringing!

What's the form here? And should the UK supplier be suggesting a 'pushfit' solution that will get tiled over?

Many thanks for any insights.

[Théière]

Surely do!

I gather your research will be from American sites where in some States it's written you can't in the plumbing code so they would add a flange fitting from each material that screws together via a union.  It's because of different expansion rates, there is the legend of the transition glue which can glue both and can be used in some States. They are a strange lot anyway, in NY you can wire your house yourself but you cannot do your own plumbing?

You can use PVC glue on ABS but not the other way as there isn't enough solvent for PVC.  That means you get a slightly over solvent weld on the ABS so it should be given longer to cure before being used. Consider the number of swimming pools done with glued parts ABS to PVC and they are pressure circuits up to 2 Bar without issue so for a waste pipe not under pressure it will fine, well it would be if your pipes were the right size. 

As you posted last time and I replied to that, buy some french traps, they have some nice ones and use those.  There are some converters around in the UK but all that hassle just for a waste outlet.

Stretching a rubber fitting past it's manufactured design is to be seriously avoided, you would consider that over the safety of the glued ABS to PVC which is already on millions swimming pools?

[joidevie]

Many thanks.. And yes, much of the debate  I've read is from the US, but some also from the UK and France..

So PVC glue should do the trick then..

I actually posted on another forum and had a couple of people suggest SIKAFLEX, which I thought was strong contender as it really is astonishingly strong.. ?

Cheers.

[Théière]

Yes modified polymer sealant/adhesive like Sikaflex form very strong bonds but they must be allowed to cure fully before mechanical movement so you may have to wait a while.  I wouldn't like to comment on it's long term suitability in that situation as I have seen mould growth on the surface of constantly immersed fittings and that suggest it could be attacked by some biological growth.  Easy to clean off when you can get to it and also with "skin" fittings etc a reasonable amount of  sealant can be used to give strength, after all they glue the sides of my van on and F1 cars also. 

[f1steveuk]

I can't really help, though I am curious as to the answer! I'm also curious about "F1 cars also"???

[Gyn_Paul]

The rubber gasket/connectors with a jubilee clip on each end are adaptable to quite a range of sizes, so 56 - 50mm is probably well within its range. I bought one for my soil pipe problem (see earlier post) where access/rigidity of existing pipes was a problem and it worked fine, it was actually labeled '110 -  100mm', but both ends were identical sizes with the clips removed. I would, however, advise against putting anything rubber into a cavity (wall - he added hastily) as the mice/lerois/fuines (sp?) will happily eat through rubber as I discovered having fitted one of those light grey 40mm flexis in a vile, inaccessible corner of a stone doorway (placco fitted before the plumbing in error), only to suffer a catastrophic leak about a year later. 

Why is it leaks only occur in inaccessible places?

paul

My 100mm connector is now buried under 2 ft of soil by the way