# best way to cut 90 year old cast iron stack



## GO Remodeling (Apr 5, 2005)

I've snap cut a few 4" cast pipes before with mixed results. Some have snapped great. But some have shattered. Any tips or better cutter methods would be appreciated. Or are special sawzall blades better than snapping.


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## griz (Nov 26, 2009)

Most if not all the major players make a sawzall blade for cast iron.

They work well.

Depending on your situation a cutoff wheel will work.

I've always had pretty good luck with a snapper.


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## ohiohomedoctor (Dec 26, 2010)

+1 to the snapper.


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## Tom Struble (Mar 2, 2007)

i like the snapper too..:turned:


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## Red Adobe (Jul 26, 2008)

I wrap some tape around the cuts and use a med tooth sazall blade..... cut 1/2 one way then switch to other side. Clay pipe same but use fine tooth and very little pressure


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## overanalyze (Dec 28, 2010)

I have had good luck with a snapper but if I can get all the way around with a grinder I just use a cut off disc.


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## Irishslave (Jun 20, 2010)

If it's really that old chances are rust has made it to about the last 1/8" or less.....Sawzall blade (slow speed) till you get the "feel" or grinder w/diamond cut off


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## GO Remodeling (Apr 5, 2005)

Irishslave said:


> If it's really that old chances are rust has made it to about the last 1/8" or less.....


That's what I was wondering about. The cast iron that I shattered was old and very rusty.

Any particular blade for sawzall?


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## Eaglei (Aug 1, 2012)

The older the cast iron is it becomes brittle and that can result in a poor cut with a snap cutter . You may get better results with a grinder and finish it up with a sawzall if you don't have access all the way around .


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## GO Remodeling (Apr 5, 2005)

Metal wheel for grinder?


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## KillerToiletSpider (May 27, 2007)

A porta band will go right through it.


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## griz (Nov 26, 2009)

KillerToiletSpider said:


> A porta band will go right through it.


Yes, if there is room.


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## TNTRenovate (Aug 19, 2010)

I've used a grinder with a cutoff wheel. I like Sait wheels. If you can fit it in the spot, Killer has the right idea.


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## aptpupil (Jun 12, 2010)

grinder


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## MarkJames (Nov 25, 2012)

olzo55 said:


> That's what I was wondering about. The cast iron that I shattered was old and very rusty.
> 
> Any particular blade for sawzall?


http://www.lenoxtools.com/pages/double-tang-diamond-reciprocating-saw-blades.aspx


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## MarkJames (Nov 25, 2012)

The cast I encounter seems always be of the extra pita variety....up against a wall or in a corner. My plumber does it, but if there's no chain cutter space, then grinder 3/4 around, and finish the rest with a cast iron blade.


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## GO Remodeling (Apr 5, 2005)

MarkJames said:


> The cast I encounter seems always be of the extra pita variety....up against a wall or in a corner. My plumber does it, but if there's no chain cutter space, then grinder 3/4 around, and finish the rest with a cast iron blade.


This will be the way I have to cut it. 

Thanks guys for all the advice.


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## Inner10 (Mar 12, 2009)

griz said:


> Most if not all the major players make a sawzall blade for cast iron.
> 
> They work well.
> 
> ...


A sawzall blade is by far the slowest way to cut a cast iron pipe....but if there isn't any room they are a blessing.

A nice thin cut off blade on a grinder will make short work of it.


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## GO Remodeling (Apr 5, 2005)

well that was 4 hours of cutting with a grinder and sawzall.

The cast had a 2x4 1" to the right and two soft copper pipes behind and 1/4" to the left. The section to be cut was near the top of a 9' ceiling.

My first cut was with a circular saw with metal cutoff blade across the top and bottom of cast. Went only about 1/2" into the pipe. Switched to grinder to lengthen cut. Then cut vertically to connect the horizontal cuts. Put a piece of sheet metal in the bottom cut to prevent anything from dropping down stack. Then cut a small corner out of the pipe. With the corner opened, I was able to attach needle nose vise grip to next piece I wanted to cut. Continued to sliced horizontal cuts then connected the top and bottom cuts to remove pieces. Each piece was about 11" long by about a 5/8" wide. A some point, the grinder body got in the way so switched to sawzall. That was a lot slower. With half the pipe removed, I was able to pry the soft copper away from the cast enough to cut the back of the pipe in one big chunk.

I have an increased respect for the Plumbing trade. Working above shoulder height with tools and cutting iron pipe with pipe lining (ie. ****) dust was no fun. I was beat when I got home that night. But mission accomplished.


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