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
SimonA1425 days ago
JimSanders3 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.94 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.

SimpsonD110 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)  keelytm3 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!