Cutting clay pipes

[andrewdbarrett]

the gravel channel between my house and patio started disappearing recently and on investigation found hole in clay drainage pipe at and just below collar where cast iron soil pipe meets. Have partially excavated around and will dig out properly on this weekend on a rare Saturday "off".
Am aiming to fit a band seal. Whats the best way to cut the clay pipe? Have 9 and 4 inch grinders or could hire pipe cutter. Is pipe cutter likely to give clean cut on an already damaged and old (1930's house) clay pipe.
Can you describe fitting of seal and how much clearance do I need to cut out to get the seal into the gap between the 2 pipes?
If the cutting of the pipe goes a bit pete tong can i insert a length of plastic pipe with a seal at each end. If so what seal do i need for cast iron to plastic?
Thanks for your help
Andy

[seanandruby]

If its not the actual bend then it should be a short piece of pipe into the collar of the bend ( fingers x ) if its deep then hopefully there is a fail safe at the top. ( short piece of pipe incase of such situations, not everyone did that ) if not then id go for mechanical cutting. we used to cut the old clay by holding a stone on the inside and tapping around the pipe outside in line with the inside stone, no fancy cutters in those days zzzzz. you can get adaptors from a B M.

[Tony McC]

Pipe cutters are quicker and cleaner, if you have the brute strength to use them.

Can't understand why you want to use a band-seal coupling when it would be simpler to break out the broken clayware pipe and replace with new.

[seanandruby]

......... if its already cracked pipecutters will shatter the rest. also can you get them down the pipe far enough?

[Dave_L]

Yeah, I was wondering about space aswell Sean.

Rip the section out and replace with new, hopefully no below ground cutting required. Above ground cutting with a 9" wheel will be easy.

[Tony McC]

In a tight space, pipe-cutters can be quicker and easier than a saw or disc cutter. The problem with most saws is that their 300mm dia blade usually doesn't cut right through a clayware pipe without coming at it from at least two angles. However, with pipe-cutters, it's simply a matter of threading the cutting-chain under the pipe and back up the other side, and then applying pressure.

Admittedly, it's not always easy to get the chain under the pipe, but it would be my first choice: I'd only use a saw if there was no chance of getting the cutters in there.

[seanandruby]

I would agree if the pipe was horizontal. but that one must surely be vertical. small 4 inch cutter would be the tool for the job.