Picture of 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:
Pipe Cutter
Couplers (correct diameter)
Extra length of pipe (correct diameter)
Non Lead Solder
Hunka Bread
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Step 1: The Situation

Picture of 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

Picture of 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

Picture of 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

Picture of 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.

Step 5:

JimSanders2 months ago

That's a great and cheap solution! Why bother with more expensive or products that serve only that function when you can just run to the cupboard and grab a slice o' bread. I'll keep that in mind the next time I've got a leak to take care of. Thanks for the tip!


guy.merritt.93 months ago

I've been using bread forever - you can use a grain bread but it disintegrates more slowly and clogs up the aerators (the little screens) on the ends of your kitchen/bathroom spigots. I guess the grains swell, or something. In a pinch, you can use a whole grain bread, though. Just don't panic when your spigots don't work - just unscrew the aerators and clean out the plug of bread.....

Part of bread has a greenish tint.

SimpsonD19 months ago

Just used a bagel, worked well! First 2 attempts without bread failed as the pipe continued to drip and the solder would not suck in.


Pa19631 year ago

It shouldn't matter what the angle is when soldering copper. There is something called "capillary action" going on. It means that when you heat the copper and apply the solder, it will be sucked into the joint, no matter the angle or direction.

MaskMarvl2 years ago
Great tip... I could have used this a while back. :)
sharpstick2 years ago
Great trick.
I'm a lousy solderer too. I had a friend come over to do some vertical pipe caps recently because I didn't trust my own skills to get the solder to run uphill into the joint. He brought over presoldered fittings. (Maybe they were only pretinned. At any rate, they worked much better. I've never seen them in the home amateur hardware stores, so I suspect they came from a plumbing supplies store.)
badpanda (author)  keelytm2 years ago
Thanks for the comment, glad to know people are still reading this trick. When I was 17 I worked for an old school Mormon carpenter who built custom homes, and I'm not talking "custom" like it's thrown around today where you get to pick your paint colors and flooring, I'm talking Southern Living magazine deep south plantation style custom, with stables and guest quarters and such, and he only built or restored one house at a time. He showed me that trick when restoring a historic cabin for a professor at UGA. I went into the Marines after that job and he wrote me at boot camp and again after I shipped overseas, a real great guy who showed me a lot of tricks of the trade that have stayed with me for 20 years and come in useful innumerable times.
Takelababy3 years ago
My hubby, a welder, asked for a piece of bread to sweat a barely dripping copper connection. We don't eat white bread so I handed him a piece that had various cracked grains in it. It worked, he did a beautiful job but upon turning the tap on, no water. He was stumped. I don't know why I removed the tap aerator but there was the bread, a solid mass, the grains having swelled solid. We were laughing so hard he could barely see to dig the mass out of the spout. So don't use whole grain bread.
streetrod53 years ago
My favorite plumbing trick! I've used this for a few years, and it's great when you don't want to wait 3 hours for all the water to drain.

Just watch your fingers when shoving the bread down the pipe; I've cut my fingers twice - now I like to use a blunt-nosed object like the fat end of a punch, or a wood dowel.

Wonderbread or white bread is the best; if bread is dry or has nuts/berries/twigs, it will be harder to ball up and shove down the pipes. And it will take longer to break down; you'll be digging junk out of aerators for days!
heathbar643 years ago
I've used the bread trick before and it really does work. I ate the crusts off first because i was afraid they would plug up stuff too well. ( besides I was hungry)
Only problem was I plugged up the shower head with bread when I turned the water back on. Should have taken it off before I flushed the pipes.
sconner13 years ago
Great tip.
badpanda (author)  sconner13 years ago
rimar20003 years ago
Interesting, thanks for sharing.

Years ago I used ground paprika to fix a leak in the car's radiator. It is an old road trick. It works!
badpanda (author)  rimar20003 years ago
Thanks... good tip with the paprika, did you just pour some into the radiator and it sealed the leak or what? I haven't heard that one.
Yes, you must put a soup spoon of paprika (Spanish: pimentón molido) in the hot water when the motor is running. After a few seconds the little flakes of paprika clog the leak. The fix is valid for some hours or days, you must fix "really" the leak soon.
Obviously, that works only for little leaks, that are more frequent.
so it is kind of like cracking an egg into the radiator to stop a leak .. it is by no means a long term solution to the leak, but it should get you to where you need to go to get the leak truly fixed .
That of egg I didn't know. It is easier to get an egg than paprika, I suppose.
sounds like the paprika will work if it is added to the radiator regardless of the temperature of the radiator. The egg only works if the radiator is hot.

sorry about getting the commets off track badpanda. Great instructable.
badpanda (author)  Lorddrake3 years ago
It's all good... spread the knowledge.
badpanda (author)  Lorddrake3 years ago
Thanks guys.
ahooper3 years ago
Use silver solder instead and you will get a better joint. Also it would not be a good idea to do this on the main feed to the hot water cylinder. Another option also would be to sleeve the joint so as to make it stronger.

As for radiators. I have used Egg, Pepper and once when I got really desperate curry powder. The egg one is simple, separate the white and drop it in to the radiator. fire up the engine and it will clog the hole. Same deal with the powders as they mix with the water and are ejected out the hole eventually clogging it.
Something people forget to do that makes this fail however is to put a match stick under the pressure part of the radiator cap so your radiator will not build up pressure to blow the seal out. It is a temporary fix.
badpanda (author)  ahooper3 years ago
Thanks... in this application I did use the sleeve, referred to as a coupler in the instructions... were you referring to something else I don't know about? What I used is a collar about 2" long made for the 1" diameter pipe I had crack here. I used silver solder here too... the lead free variety, just because I assumed it's bad to have lead anything in your plumbing/water.

The match stick knowledge on the radiator fix is something I definitely would not have known but makes total sense. Thanks!