Home>Discussions>PLUMBING>What's a good way to cut cast iron pipe in a tight space?
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jalbes
What's a good way to cut cast iron pipe in a tight space?
jalbes

I'm putting in a basement bathroom, I've broken the concrete floor open and located my sanitary line.
For my plumbing to flow correctly, I need to tie in at the lowest point of that sanitary line (where it runs horizontal under the footing) and install a Wye connection for my new bathroom requirements.

My problem is...
My vertical sanitary line elbows 90° directly under the footing, limiting me from using a chain pipe breaker, sawsall or angle grinder to remove that elbow. The elbow is just too deep under footing to reach with any long tools. I almost need something like a heavy duty Dremel tool to cut sideways.

Any suggestions?

bill
Re: What's a good way to cut cast iron pipe in a tight space?
bill

some times i have used a disc grinder with a cut off disc.

bill
Re: What's a good way to cut cast iron pipe in a tight space?
bill

also it is not good plumbing practice to put joints or fitting under a footing. I would remove what is there and rework the configuration to some thing that does work. Also a 90 bend shoud not be at the bottom of a stack, instead two 45 degree bends should be used.

Bill

Fencepost
Re: What's a good way to cut cast iron pipe in a tight space?
Fencepost

If you can dig down to the line outside the foundation (probably not possible in northern areas this time of year), cut it outside, then add a stub to the sweep tee you'll be putting in so you don't have to work under the footing.

That is, add a 2-foot or so stub to the outlet of the tee before you stick it under the footing.

Be sure to put a cleanout above where the vertical pipe dips into the floor, so you have a convenient place to snake the drain in the future.

https://drive.google.com/file/d/0B-bDEAwz5EuTcUlJUzk1MVljMEU/view

ZZZ
Re: What's a good way to cut cast iron pipe in a tight space?
ZZZ

If you had asked before you cut the floor and dug it up, I would have recommended a sewage ejector pump/basin system. Of course you would either have to raise the bath floor 6" or cut the concrete a install a below-ground system.
Since that was not what you asked about, the best choice is probably a 4" angle grinder. Proper venting will also be important, and a cleanout is required either before it leaves the basement, or at grade just outside the building.

RobmanQ
Re: What's a good way to cut cast iron pipe in a tight space?
RobmanQ

A grinder with a 3 1/2" or 4" metal cutting blade should do it. Just make sure it is a thin cutting blade, instead of a thick grinding blade. Sounds like you may never have used one, and if that is the case, I cannot stress enough how important it is to respect a grinder spinning at 11,000 rpm. Make sure you have the handle on it to control it. Make sure it has the guard on the blade, sometimes they are a real pain, but if you can cut it with using the guard, do so. Make sure you wear thick gloves, or double them up. Also hold the grinder very firmly, and do not force it or make sudden moves, it will kick back otherwise. Also make sure when you cut the pipe, it is on the face where the pipe will open up, otherwise it will pinch the blade and cause a kickback. It is similar to using a chainsaw with that respect. If you are forced to cut on the face of the pipe where it will pinch the blade, make a half cut with the cutting blade, switch blades to a grinding blade, open up the cut so it is wider, and then switch back to the cutting blade to finish the cut. Hope that helps.

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