I need to remove about 6 feet of cast iron sewer line in the basement due to a sag in the middle caused by a leaded joint in the middle. The section terminates on either end with another leaded joint I am worried about compromising. The local tool rental stores around here say use a snap cutter but the only one available is too big for my job (the 4 inch pipe is up against the basement concrete wall.) Cutting with a Sawzall is a study in ruined blades. Any solutions?
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BIG hammer.
With ALL safety gear in place hold a BIG hammer on one side of the pipe. Now hit the other side with a second big hammer. Get help. it's easier that way. Make sure helper has ALL safety equipment, etc.
Then when you get close to where you want the actual cut use a 10" or 12" adjustable wrench to finish the cut. Close it to just a bit wider than the pipe wall thickness. Slide it over the edge of the pipe and snap it off. Keep doing this until you have a fairly straight edge.
If the pipe is rotten it may split all over the place. Be prepared to call a pro at that point. It would be much safer that way anyways. It is about a 20 minute job if all goes well and the pipe is easy to get too.
Not true about the Sawzall. A Sawzall is all I've ever used and I've done it at least 20 times. Just use a new metal cutting blade. I like the wide ones they call the "Torch". A new blade will give you at least three full cuts before needing replacement.
Good luck!
I think there are differing qualities of cast iron. I have cut quickly through a cast iron pipe with a sawsall but there are other pipes that stick in my memory that just laughed at several of the best blades. Perhaps this is one of them..
Excellence is its own reward!
My old pappy taught me techniques as a kid how to do it with hammer and cold chisel, whether by hand or air impact chisel - just like cutting glass, only lots more force. However, took about 10 cuts before any skill developed for confidence of getting a clean perpendicular cut.
What do you want to do, just smash it out and replace with rubber joints and plastic? - then the hammer method is my vote.
Another option is to simply jack into line, support, possible relead/recaulk if it leaks or maybe just packing down the lead with hammer and packing spud.
and then support it at the joint!
When I cut mine, it was against the wall also and I was still able to get in there and cut it w/chain cutter. Make sure it's supported above so the whole pipe doesn't come crashing down on you!
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I had reasonable luck with a sawzall doing this sort of thing. Go slow and lube the blade. Keeping the blade cool will keep the teeth from losing their temper. When I did this, we actually used spray vegetable oil to lube the blade so as not to send petroleum based lubricating oil down the sewer.
"Cutting with a Sawzall is a study in ruined blades. Any solutions?"
I've had that happen to, but other times they (cast iron pipes) cut like butter. There are all grades of iron out there and sometimes even have sand in the castings. But you can also work harden the metal as you cut by continuing to use a dull blade making matters worse. I still have yet to experience a pipe that a NEW bimetal cobalt blade wouldn't cut. IMO try a really coarse blade. Two reasons for this, first more tooth pressure and two, even if you don't cut the pipe you will "chip it away." Don't forget to adjust the pawl as you go to maximize blade life.
Jon
sawzall with the right 4 or 6 inch blade - goes right thru -- did a couple this past January -- takes time but it is far esier and exact than by hand
Jon------Thanks for your prompt reply, I will proceed with the feeling that I am taking the proper approach------Gramps
Milwaukee lists their silicon carbide grit blades to be used for cast iron as well as for vitreous materials.
Ken Hill
never tried those but I have cut many with a Sawzall without a problem. Ruined a few blades but they were just part of the cost.
Ya, "The Torch" blades.
Ken Hill
I do it a different way - and I have to do it in my house, too, now, because my bathroom sink is plugged & I can't get the cleanout apart.
I use a 4½" angle grinder (it's what I own) with the best quality steel blade I can find, and the fire extinguisher right there.
Always worked for me.Quality repairs for your home.
Aaron the HandymanVancouver, Canada
I learned something today.
I have both the angle grinder and sawzall, and for metal I generally go for the grinder first. Haven't done the math, but my gut feeling is that the grinder cuts more square inches of cross section per dollar spent on disks vs. sawzall blades. Depending on obstructions, sometimes the best thing is to do most of the cut with the grinder, and then go to the sawzall to finish the part where it won't fit. The nasty thing about the sawzall is hitting the end of the blade on the far side of the pipe. Check carefully and don't let that happen.
-- J.S.
Ken
I just also used that Milwaukee carbide blade to cut through my cast iron pipe in two places. Worked fantastic. Says right on the package that its for cast iron pipe. Kinda expensive but its still got plenty of life in it after two cuts. Sure is cheaper than a trip to the rental place and I got into some tight spots with it.
a
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I second or third the the carbide Sawzall blade approach. Mine were Remington brand, I think, and I got them at Home Depot. They cost about $8 for two. One should make both cuts for you. I also agree with the suggestion to support the remaining pipe. You don't want it cracking. Old iron pipe can be brittle.
Al Mollitor, Sharon MA
I was helping my best friend add a toilet to his plumbing stack, and had to make two cuts in the cast iron for the tee, I had brought several good "torch" blades with me and and burned them all up without getting deeper than an 8th inch. (I've cut cast iron no problem several times with these type blades)
Not to be deterred I sent him to the store to the store to pick up some more. He comes back with the blades and pack of the Remington carbide grit blades. "It says they're good for cast iron" he says.
I give him my best "I'm a professional" look and say "I've tried the carbide grit for ceramic blades that they make and they suck" (which they do) "thoes things are worthless."
After I burned another blade without making any progress, his wife called him upstairs to help with something. I stuck in one of the carbide grit blades and gave it a try, and it cut right through.
He was very gracious, and has only reminded me about ten times. :) Justus Koshiol
Running Pug Construction
That was my experience with the Remington blade. For those who may not understand what these blades are, they are blades that fit in a regular Sawzall. They don't have teeth, but rather, a carbide grit on the cutting edge. I guess it's like an abrasive bit on the above-mention cut-off saw, but with a sawzall, you can cut in just about any position, with no need to rent anything.
Al Mollitor, Sharon MA
I gotta try one son!
The Rotozip has an 90 degree angle fitting that straps on where the bit usually goes and runs a circular metal or mortar blade - about 3" diameter. It's a smaller blade than the grinder - but it might fit into tight places the grinder won't get to - and you can control the RPM on some models. Goggles and Gloves - especially if the cast iron is brittle. Not to mention the possilble infections from the contents if they got embedded in your eye... (Some of us DIY types use the rotozip with the metal blade to cut copper or even PVC as well ;-) - as well as using the regular drill fitting to "zip" out the tile for taps.
Gavin Pitchford
the tool rental store should have a hand held abrasive blade cut off saw the two brands I have used over the years are eirther a black and decker or makita,just one word of caution watch out for the sparks.other than goes though the pipe like a hot knife though butter
Thanks for your insight. This makes perfect sense as the last time I cut pipe in the same house (outside actually) I gave up on the Sawzall and finished the job with my Makita grinder. Space is the issue this time. Thanks--------Gramps
Nobody has mentioned the ....stuff... that comes out of the cut and gets all over your sawsall.
Any tool you use make sure you put plastic down, have buckets in place, and wear the safety glasses.
14 inch gas cut off saw, diamond blade for cutting HARD concrete, fire extinguisher, gloves and glasses
wrong tool, wrong blade, be carefull
4 inch CI pipe in 15 seconds
Now that's a REAL man!!!Quality repairs for your home.
Aaron the HandymanVancouver, Canada
Hmmm -- why not try shaped charge explosives? ;-)
-- J.S.
I've noticed that the methods of cutting cast are getting increasingly agressive.
Tell me the name of the hospital where I can visit.Quality repairs for your home.
Aaron the HandymanVancouver, Canada
I have used a 12 or 14 inch cut off saw ( chop saw) to slices right thru cast iron or anything else for that matter. I have used it numerous times on cast iron. It should take longer to start the saw than to cut through the 4 inch cast. I have been using a cut off saw all week to cut 48 inch ductle iron on a 20 million dollar water treatment plant job i am working on. They cut anything you can throw at them. You should be able to rent one at a local tool rental for about 25 $ a day