Cast iron bath/basin waste pipe fitting size?

[Pete321]

Hi,

Helping a friend, his soil stack is cast iron. The bath and basin wastes (all removed now) went into individual entries on the stack. These are iron pipes, with what looks like a female internal thread into which there is some sort of metal reducer with what is maybe a compression fitting. The plastic waste pipes that are now removed went into this, but they didn’t seem like a particular good fit. The hole in the nut measures approx 35mm.

Does anyone know what we should really be looking at to connect the new bath/basin waste pipes to these iron pipes?

Thanks,
Pete.

 

[Deleted member 120897]

Hard to tell from photos, but could you use a McAlpine universal coupling? Can you post photos of waste pipes from further back?

 

[Pete321]

Hard to tell from photos, but could you use a McAlpine universal coupling? Can you post photos of waste pipes from further back?

Does this help? These are the pipes, they come out the stack, have a 90deg bend and then the final fitting. The nuts have been removed from both.

I’d say these the fattest part is getting on for 55-60mm and I’m presuming it has an internal/female thread into which the next part is screwed.

 

[Deleted member 120897]

Does this help?

Yes and no. Better to help understand, however I’m unsure of how to connect those up. Probably need a specialist fitting.

 

[Timmy D]

Looks like a 35mm Male Iron threaded into that elbow. Also looks like you’ve remove the nut and olive between the two pics.

If I’m correct, either you put a stub of 35mm copper into the compression with the nut and olive and then a 35mm coupling to bulk it up (to Male the next fitting fit), then a 1.5 inch compression waste fitting to connect your 40mm waste pipe.

Or you might be able to wind out the rest of the Male iron which is still in the elbow and wind in a solvent weld Male iron. But this would be in 1.25 inch and need to be stepped up. Not ideal.