Introduction: Using Bread to Sweat a Leaking Copper Pipe
This Instructable shows how to use white bread and standard pipe sweating techniques to repair a leaking copper pipe. There are a ton of excellent instructions online and here at Instructables for pipe sweating, this isn't meant to replace those, but rather to show a trick I learned over a decade ago for sweating a pipe that is actively leaking. Normally you hope that by cutting off your mains and draining your lines you can eliminate any water leaking from the pipe you're trying to sweat. Sometimes you can get any extra out by using a shop vac. But sometimes you're screwed and a persistent drip will make it nearly impossible to do a proper solder because boiling water coming through a seam doesn't allow for the solder to set where it should. This is a cheap work around. There are commercial products that produce a similar result, usually wax plugs or other things that melt away as you sweat. That might work, but I have to imagine some wax is left behind because by the time you turn the water back on the wax won't be liquid anymore, but I digress.
I apologize if my pictures are a little dark or blurry. I had to do this in the dark while it was raining on my back, but we don't usually get to pick when these things happen, so I'm just glad I remembered to take photos at all.
Tools and Materials:
Couplers (correct diameter)
Extra length of pipe (correct diameter)
Non Lead Solder
Step 1: The Situation
If you saw my last Instructable on making Motorcycle Saddle Bags out of 40MM Ammo Cans there was a step in which we sprayed down the cans with paint stripper and then rinse them with the hose. Well, if you've ever watched somebody walk off with a garden hose that hasn't been secured to anything other than the faucet itself, you know what's about to happen especially if that faucet is sticking way out. Some copper is about to get mangled. Secure your hoses between you and the faucet. Then maybe you won't ever need this bread trick.
In this case I noticed a pretty good twist in the pipe right against the wall and a small crack that was leaking water, and this is right above my main. There are other Instructables on patching pipes, making the cuts, and sweating so I'll move fast through those parts. I'm not trying to compete with those and they are excellent, I'm just showing a trick for doing it when leaky. So I punched out a bit of wall and cut out the bad section with a pipe cutter. Use a pipe cutter, as much fun as power tools are, they and copper piping do not go well together... you will not get straight cuts and straight cuts are crucial to prevent leaks. Most copper pipe cutters cost less than 10 bucks. I bought one today for 8.50 after realizing what a disaster my grinders metal cut off wheel was making. Use standard sweating techniques to put a new pipe section in and the couplers needed, right up until the last bit which never quite quit leaking. I tried for about 5 minutes to sweat this piece on before realizing it would be impossible and remembered this trick my old boss taught when I was a kid working a summer job.
Step 2: Pipe Preparation
Just like when normally sweating a pipe, clean it up with plumbers cloth. You can use emery cloth or whatever normally, but emery cloth tends to deteriorate as soon as it gets wet and you need to clean up the leaky side. Use a pipe brush to clean/mar the inside of the coupler as well if you didn't hit both sides of it on the last sweat. Brush flux on the outside of the leaky side and the inside of the coupler. I know I could have done a better job on the clean up here, but I had just banged my head into the garage door and it was raining, so there was quite a bit of swearing and not giving a crap happening right about here.
Step 3: One Way to Use Bread That Won't Make You Fat
Crucial: Before you put bread in the pipe have your torch and solder at the ready. This will only give you a few minutes of grace time before the leak starts again.
I only had some white bread laying around that I baked last week. It's delicious bread and I'll have to make that into an Instructable one day too, I'm a much better baker than a plumber. Anyway, this was a thick end cut off the loaf that was left. You need probably about half to three quarters of a piece of Wonder Bread to give you an idea... maybe a little more or less depending on the volume of your leak. If you're getting a lot of water to the point where this doesn't work, you've got something else going on... figure that out first. You need enough bread to absorb the leak for a long enough period to complete the sweating. I used this amount of bread and this is a 1" pipe and it worked fine.
Stuff your bread into the pipe on the leaking side. Stuff it in as far back as your finger will reach.
Step 4: Sweat
Shove the pipe into the coupler and sweat it with your solder. Other instructions will let you know, but I will repeat, you don't melt solder with the flame, you melt solder by heating up the joint until it is hot enough to melt the solder by touching it with it. If you try and heat the solder with the flame and just sort of paint it on you will become extremely frustrated with how badly this is going for you and very likely light yourself on fire to bring an end to madness.
Yes my soldering is ugly, cut me some slack. It was raining and dark, I was drunk and had a huge knot swelling up on my head and I'm no plumber. The solder held so I'm happy. Tomorrow I guess I'm cleaning up this hole in the wall.
Let the pipe fully cool off, to the touch, before kicking the water back on. Don't try and splash any water or anything on it to speed up the process, this might shock your whole mess and result in another leak. Once it's cooled off put pressure back in the pipe by turning on the water main, and open your hose valve and bread bits may or may not shoot out. If you have a little filter in there you can take that out and speed up the process, but the bottom line is the junk trapped in the pipe is bread and will pretty quickly disintegrate and get out of your system.