Bathroom blockage near soil stack - need advice

[Patrick Denom]

The blockage is near the soil stack where the red x is

The bit where the block is 40 years of calcium deposits- seems rock hard - I removed the mcalpine connector and tried with a rotary drain auger to break through it - no success - too much resistance- I’m in Surrey - a very hard water area.

Although I can’t say for certain it’s limescale (because I can’t see inside) , it seems plausible that it is because some other parts if the system like my bath u bend had rock hard deposits in previous years

Any hints to solve it ?

Chemicals won’t work because it’s only 99% blocked and they would drain away

I’m happy to cut it yank out the limescale , and then recreate the the joint , but not sure where to cut etc

I was also thinking of drilling a 10 or 12mm hole strategically and getting at the limescale with a sharp screwdriver slowly , and then when done fix the hole with a good epoxy like milliput

Any suggestions- the joint indeed looks dirty on outside after 39 years

 

[Koolpc]

You need 1.5 sticks if dynamite...

 

[HERTS P&D]

What rotary drain auger did you use?

Andy

 

[RrogerD]

Although I can’t say for certain it’s limescale (because I can’t see inside)

You could use an endoscope. £30 from Toolstation. I have this one and find it pretty good. Better than others I've tried in the past.

https://www.toolstation.com/draper-endoscope/pAA096

 

[Hugh Jaleak]

Boss will be Welded to the stack, I'd be wary of trying to do anything with it unless you're confident on replacing a damaged section of the stack below the junction...

Chances are its scale build up, it may just be a case of slow and steady wins the day, once you can get going I'd expect the scale to start breaking up reasonably easily. A Picote machine would probably make light work of it, might be worth asking about if any local Contractor has one and could quote to do the job.