Soldering Copper Pipes

Mar 21, 2005 69 Replies

Go for it. It isn't brain surgery. Just buy a few extra fittings, and a couple extra feet of pipe, so you have something to practice on before you tackle the real thing.

One thing I'm not sure I've seen anyone mention yet in this thread: apply heat to the _fitting_only_, not to the pipe. The idea is to expand the fitting slightly, to make a larger gap for solder to flow into -- so that when it cools and shrinks, you have a tight and leakproof joint. There's enough contact between the fitting and the pipe that the pipe will get hot enough to melt the solder even without being heated directly by the torch.

Then apply solder to the _pipe_ just outside the joint, but not to the fitting. If you have everything cleaned, fluxed, and heated right, the solder will melt and flow into the joint.

-- Regards, Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?

Right on with using MAPP. For drinking water you should use 95/5 solder. This requires the use of MAPP. Not using it will just waste your time.

If this was for hot water heating, 50/50 is still used and propane work just fine.

Tom

P.S. Please note that when using any solder and pipes overhead make sure to either watch your arms or cover them with something. (this really goes for anything else that is attached to you) Solder heated up with MAPP or Propane hurts like a bitch and leaves some interesting marks on your arms.... Yea, i've learned that lession the hard way! OUCH! 3 scars on my arm and counting...

I'll settle this on Saturday and let you know. Worst case: I end up with a propane torch that'll be useful for lighting the newspaper in my BBQ chimney starter in a high wind, when matches and everything else fails.

It doesn't hurt near as much as popping molten slag while arc-welding.

Joe

Ditto the MAPP gas.

I will never use propane again. My investment in a mapp gas torch/bottle was about $25 at Lowes. It works *much* faster than propane and if there is a little moiture left, it can be hot enough to overcome that.

It's not that hard and it's a good skill to have in your arsenal.

-s

Hand torches come in quite a range of sizes and styles. A turbo torch with propane easily puts out enough heat for lead-free solder on 1" copper pipe. MAPP puts out more heat, no doubt, but propane in a properly-sized torch is more than adequate. You can even braze with propane given a torch sized appropriately for the work.

It doesn't either. Propane works just fine.

-- Regards, Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?

TO HELL WITH IT ALL. Get some Copper-Bond, a 2-part epoxy made for the task, and damned good at it, replace the squarish sticks with Q-tip sticks without the cotton, and do the joints. A 2 liter bottle cap makes a pretty good mixing container.

It is a bit tricky to get soldering right, but the good news is it's very cheap to get a book and a little spare copper pipe and fittings with your purchase, and then practice on your workbench until you've got it down pat.

I've not used this....how easily does it come apart when the time comes? Or do you just cut the section out?

Joe

I just read some of the comments about MAPP vs. propane.

I use a propane torch on all my copper water piping, no matter if it's domestic or boiler work. I also use 95/5 on everything. There are times that if you don't pay close attention to the flow of the solder, you'll cook the joint and either have to use silver or totally cut the joint out and use additional fittings.

The only time I use MAPP is for using silver solder for refrigerant lines.

I just finished a job that I used a propane torch on piping up to 1.25". It may have meant the job taking 20 minutes longer,but I felt it was worth it.

What do you mean by "cook the joint"? Actually melt the bejeezus out of the pipe ends? Or does excess heat ruin the surface of the pipe, making it unable to accept solder correctly?

Yes. In my experience, too much heat/time will drive off the flux and oxidize the surface, if solder doesn't get there in time. The answer is to start over, cleaning the surface and refluxing. --Phil

I'll have to agree with that. I've used a propane torch on the same types of copper and have had the same successes that you have had. Soldering copper pipes is almost as much an art as it is a mechanical project, and a degree of carefulness is as relevant as with just about any other art.

The time never comes to take it apart.

I had used a torch, and was quite good with it. No fitt> > Get some Copper-Bond,>

I'll admit, back when I was starting out, I cooked a couple of copper solder joints. No amount of sanding and fluxing would bring one of those back, so I had to add a coupling

"HeatMan" wrote

Soldering copper pipe is SOOOOOOO easy once you get the hang of it. But I would say the most common mistakes are too much heat, poor cleaning, and no flux.

It is a breeze with good cleaning, a little flux, and the right amount of heat. What a lot of people do is put the heat in the wrong place. Heat a little away from the joint so that you heat up the pipe, and let the solder flow and be "sucked into" the joint.

Not rocket surgery, but a little tricky.

Steve

Sounds exactly the same as soldering wires & circuit boards properly.

The opposite of how I was taught by a guy that soldered hundreds of joints in heating coils all day long. Heat the fitting, not the tube to suck in the solder.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required