So lately we've been demolishing some interior things, like walls, trim, windows, and obviously from the title of this thread, pipes.
The original windows were probably made in place, and utilized cast iron window weights to balance their operation. I've already rid the project of most of the window weights to a guy I now know as "Lance Scrapper" in my mobile phone contacts. He said cast iron was about $200 per ton. A ton is 2,000 pounds, which makes for approximately 400 - 600 window weights depending on their size. Each weight is stamped with a weight factor that relates to window size. I think these are 3 pounders:
Let's put it this way -- I'm not taking 600 window weights to the scrap yard. Period. So this guy emailed me from craigslist as he was interested in my scrap metal "boat anchors" as I call them. I also gave him an old cast iron sink that weighed about 150 pounds by itself. Bonus day for Mr. Scrapper.
Anything useful, such as trim "shims" (extra strock for who-knows-what purpose), wood studs or other salvagable items are being kept on site and out of the dumpster - for now. Anything metal will be offered to Lance Scrapper once most of it is piled up and ready for transport.
It hasn't taken long to get fairly clean, but being clean means a heckuva lot of trash has gone into the 20 yard dumpster I just got last Wednesday. I thought we'd still have a little room for roofing material, but I guess we'll just have to get another.
And now for Sunday's most excitingi task -- removing the old cast iron soil pipe. This pipe unfortunately was rusted through at the very base, which would either require some kind of seriously tricky repair or simply complete replacement. I chose for the complete replacement.Replacement is good for a number of reasons, best of which is that I had no idea of the condition on the interior of the existing stack and that is is inadequate for the new plumbing that is being installed.
I started by asking my plumber how to cut the pipe. He suggested the ONLY way was a chain cutter or snap cutter. You can sawzall through it if you want to waste blades and precious time. It's a serious endeavor to saw through cast iron, especially a 4" drain stack. You don't want to bang on it too much with a sledge hammer either. The shards are pretty sharp, and it's mostly pointless. Since I am interested in connecting to the main elbow at the basement level, I couldn't risk breaking the lip of the elbow off by going wild with a sledge either. A chain / snap cutter is the gentle but forcefully answer.
The chain cutter consists of a chain with carbide blades set in between the links, a racheting axel, and a long handle to cinch the chain with great torque. The chain is wrapped around the pipe and locked into position with fittings on the cutter. By engaging the rachet mechanism on the arm, pumping the rachet arm causes the jaws along the axel to squeeze the chain together, increasing the cinch of the chain around the pipe. When the pressure becomes enough on the pipe, the pipe literally snaps in a nice, nearly clean joint.
You have to start as tightly wrapped around the pipe as the chain can get, or risk the jaws jamming up at the middle with nowhere to continue squeezing. This happened once on the 4" pipe and once on a 2" pipe (the minimum for this particular tool). I had to get a pipe wrench and spin the adustment knob to loosen the chains tension around the pipe to avoid damaging the tool. If it starts to get near the center, I've learned to stop and start over with a tighter original cinch.
The long arm of the cutter allows you to really torque the chain around the pipe. Without that torque, the pipe probably wouldn't shear. The dangerous part here is to make sure that when you're working overhead, you have the pipe secured. When it snaps, it can come crashing down faster than you can react. A five foot section of 35 lbs. per foot cast iron pipe would leave a heck of a scar across the line of your toes. Heck, have the cutting tool secured too. It weighs a good 50 pounds on its own.
I did run into a small problem in the basement where the pipe was visibly okay on the outside, but pretty thin and rusted on the inside. The cutter had so much torque that the pipe imploded on the rusted side, but didn't slice through the other. I think if you ran into that issue that you would need to secure the arm side, where there is the most direct pressure, on the most solid portion of the pipe. Finding another location from which to cinch worked for one segment that I was sure would continue to crush and implode.
Lastly, I left the last segment of pipe in place and figured my plumber could figure out how to loosen the old cast iron joint. Apparently, cast iron joints were secured with a molten lead solder and oakum, which is a fiberous material used to pack and secure the joint. The best explanation I found on the web for pipe removal was to drill holes in the lead to the oakum joint, all the way around the pipe, until you could pry out the lead. I tried this to no avail, and I wasn't interested in spending an hour on something that may or may not work.
I figure that with a plumbers torch one could melt the lead joint and pull the pipe out more easily than the drill and scrape method. But I wasn't very interested in breathing in molten lead fumes that day. We'll let the pro work on that one. Maybe in the end, with luck and the determination in removing that cast iron pipe, I will have saved the money that would've been spent on cutting the basement slab and replacing the entire elbow at the floor base.
Say hi to the "demo dog," Blade! Until next time!
