best reciprocating blade for cast iron

[dd1975]

i have a cast iron stack i need to cut into for an additional downstair wc,, the problem is the space is zero,, well tight, it is a very busy corner of the house,, cold mains, electrics, the usual carry on
the only way i think is to get the reciprocator out but i have never used it on cast and i was looking for the best blade if there is such a thing that would be up to it,,, there is no way i can get to it with a ginder or even with a hacksaw.. i'm trying to avoid the macerator route at all costs, thanks

 

[newbuildinstaller]

http://www.ebay.co.uk/itm/Bosch-S11...Home_Garden_PowerTools_SM&hash=item255a2239a5

google is your friend dont fear it

 

[Hugh Jaleak]

Ensure the pipework above is adequately supported prior to cutting, cast is extremely heavy and you dont want the lot dropping when you cut a section out!

Would it be easier to take the new WC connection outside to connect to the drain underground? There's obviously a drain nearby if the stack is in the vicinity.

 

[dd1975]

thanks very much, digging up outside is a no go as it is council ground, it's a private house but will not bore you with details,, politcs and neighbours of course thanks again

 

[dd1975]

Sorry how many blades do you think it'll take to cut the 4" cast, I see the blades come as a pair?