Splice a Tee into cast iron stack

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DIYorBust

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Hello,

I would like to add a tee to a cast iron 4" stack to run a branch for a washing machine. I'm thinking about using a riser clamp and 2x4s to support it above the cut.

I'm also concerned that I won't have enough play to get the tee and the couplings installed. Is this likely to be a problem? Am I missing anything else? I really want to be careful with this project.

Thanks!

DIY
 

Reach4

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I'm also concerned that I won't have enough play to get the tee and the couplings installed. Is this likely to be a problem? Am I missing anything else? I really want to be careful with this project.
You intend to use two cuts and two shielded couplers, right? I expect you will final-cut the PVC assembly after cutting the cast iron, and measuring the gap.

You will measure the OD of the cast iron to make sure you get the right couplers.
 

Terry

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The cut is 1/4" more than the fitting assuming you cut it square. You can get by with a little more than that too. The rubber gets rolled back, fitting placed inline, and then the rubber rolled back over the new fitting. The the shielded part slides up and over it.

You can use a snap cutter which cuts a a square cut, or use a sawzal blade designed for cast. Diablo makes the best ones.
Eve protection always.
I do not use a grinding wheel. Too much bad stuff can happen.

Sometimes I pick up a no hub cast fitting to insert there.
 

DIYorBust

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Thanks folks. @Reach4, I am planning use two cuts and two shielded couplings, yes, but I'm planning to use a no hub cast iron tee rather than transitioning to PVC.

@Terry I'm planning on the sawzall to cut this with a diablo carbide blade. I'm toast if the pipe breaks in bad way as I don't have good access to the next coupling, and I've heard that the snap cutter can damage the pipe. I guess I'll just have to be careful to cut it square. Any tips on this?
 

Reach4

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The the shielded part slides up and over it.
If you are absent minded, and forget to slide the shield on first, you can still add the shield later. It's more work than if you did not forget.
 

Terry

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You can place some tape around the pipe to added as a visual guide when cutting.
The Diablo blade is what I would use there. Snap cutting works okay on new pipe. With the old stuff it can get a little weird.
 

Jeff H Young

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Good advice above! i gotta get a real blade for cutting cast its a PITA sometimes with standard blades on saws all. I think its cleaner/better putting a cast iron fitting even if then going to plastic for something new.
The cut is critical to a degree not too much or too little!
 
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