No announcement yet.

Soldering copper pie the right way?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Soldering copper pie the right way?

    Is the guy in this video doing everything correct?

    I have done very little copper pipe soldering in the past but I have some coming up in the future and need to get it just right. What is the best solder to use for copper pipe? Separate flux or solder with flux in it? Mapp gas or propane?

    Pointers, things to look out for is all appreciated!


  • #2
    yup, he's doing a perfect job

    they always make it look so easy though

    the flux will be pasted on inside the joint.

    my blow lamp ..spits ...goes into full on mode when i tip it

    and i always end up cooking the solder

    all the best.markj
    Last edited by aboard_epsilon; 06-07-2011, 03:56 PM.


    • #3
      I wouldn't wipe the excess solder with a gloved hand. Molten solder will penetrate a porous material and could give you a serious burn, you wouldn't be able to get the glove off fast enough. I've always heard that you should use a damp rag to wipe away the excess solder.


      • #4
        Also notice the ends of the pipe has been cleaned with emery cloth, it also helps to remove the patina from the inside of the fitting the same way before applying flux and assembling. Most fittings are around wood so have a spray bottle of water handy to soak the area after soldering, just in case. careful preperation and assembly makes the job as easy as it looks. Peter
        The difficult done right away. the impossible takes a little time.


        • #5
          The two biggest secrets to successfully soldering a copper joint is #1, clean and shiny, and #2, clean and shiny.

          A good propane torch will do the job but a poor one is a PIA as the copper transfers a lot of heat away from the joint area causing everything else in the area to get hot but not the joint itself. You want a good hot flame so that you are only there for a few seconds.

          Peter had a good suggestion by keeping a water spray bottle handy, I sometimes also like to use a light gauge piece of sheet metal handy to momentarily deflect heat from combustibles.

          I usually use just a very small dab of flux on the joint as it will go a long way when it gets hot, and with a good clean joint you don't need much.
          Home, down in the valley behind the Red Angus
          Bad Decisions Make Good Stories​


          • #6
            I never had any luck with propane. I watched a guy do it with oxy-acetylene and a small tip. He made it look easier than PVC.


            • #7
              clean pipe and fitting inside and out to bright bare metal ,
              greasy paste flux a.s.a.p to limit oxidation
              with mapp torch, heat general areas away from joint to build up temp at joint
              stick the solder at the joint and bring the fitting up the the temp that melts the solder (torch not melting solder directly fitting is) solder will flow into joint via capillary action. gravity helps if you can position the part
              remove heat before flux gets cooked off

              *** If it does not work first time, stop and begin again from scratch. ***

              a tip on repairs in a old house where the shutoff valves do not shut off completely and so the pipe being repaired has a small amount of water trickling... with everything ready to go stuff bread in the leaky side a few inches back should swell up and dam the trickle long enough to make the joint. then blast it out through the tub or after removing the screen filters
              on a faucet.
              a nasty trick to have to use, but when you need it ...
              Tom C
              ... nice weather eh?


              • #8
                Originally posted by J Harp
                I've always heard that you should use a damp rag to wipe away the excess solder.

                Use a dry rag to wipe the joint. A nice thick rag is best. A damp rag will steam up, cooling the solder too fast and possible give you a steam burn.

                (don't have to ask me how i know this..)

                Appearance is Everything...


                • #9
                  Cleanleness is mandatory in soldering. Getting the right heat and controlling it is also necessary. Propane and Mapp torches work and some are much better than others. Some work equally well upside down. An air/acetylene torch works the best in my opinion. An oxy/acetylene will work but is too hot and difficult to control. If you have much soldering to do it is worth getting a air/acetenene torch and small bottle. Some flux is better than others. Talk to a plumber for flux recommendations.
                  Byron Boucher
                  Burnet, TX


                  • #10
                    Thousands of joints with a cheap propane torch here. If there is good tinder for a fire around (sawdust, a crack in a board, fuzz around a drilled hole) I spray it down prior to heating as well as after. A sheet metal shield will not only protect the surrounding material from fire but will heat the joint much faster.

                    Number one culprit in repair work -water in the line. Joint won't get above 212* until every drop of water is evaporated out. By that time the generated steam will have steamed cleaned the flux off and the pipe will tarnish and not accept solder. If necessary cut the pipe at it's lowest point to drain and repair with a soldered or compression coupling for future dis-assembly.


                    • #11
                      Great info! Anyone got some insight on a good propane torch with a single strait blue flame? The one I have now has three blue flames off in three different directions.

                      I have a paste flux now that I use for general wire, board, joint soldering but when I go out for a torch I'll look for some other new stuff.

                      All the piping will be new but I will make sure the connections are cleaned good. Thinking about it I can't come up any kind of connection that shouldn't be cleaned well before welded, glued, fusion, etc. if you want a good result. Are there any? lol


                      • #12
                        The best plumbers do a pressure test before activation of of a new system. There can be defective fittings. Carpenters have been known to put nail holes in copper pipes. There are lots of ways things can go sideways. I have even seen pressure failures from excessive pressure coupled with defects. A friend had a sunken den that became a wading pool. I came home twice with water running out the front door in a new home.
                        Byron Boucher
                        Burnet, TX


                        • #13
                          Are there test ports that can be soldered in for pressure testing? Test up to 20psi?


                          • #14
                            you need to test it to more than 20, test something above household water pressure. That is if you have an inspector to satisfy, I would never bother if its just me working on the project and there's no clumsy carpenters to worry about

                            I've never heard of wiping the joints, if anything you don't want to disturb the joint....just don't use so much next joint, the blob won't hurt anything. On workshop things being soft soldered that have to look good, I just wipe any excess off with a paper towel, dry is fine....temps are low, it won't burst into flames. This is a great way to tin a fixture btw that you want solder a workpiece to ....flux, solder, then wipe down with paper towel and only the thinnest of tining will remain

                            emery the outside pipe, plumbers wire brush for the inside, flux, assemble, apply heat to one side, solder to other, let a bunch flow when its read and you're done. Its very, very easy to do.

                            Don't use anything more than propane/air, there's no need and O/A requires more skill as its to hot for the flux and should be used indirectly, not sure why someone would soft solder oxy acetylene. Its elevated temps also don't sound very safe inside of wall cavities, kitchen cupboards etc. If you don't have a propane torch/regulator, those little hardware store tanks/torches in one work fine for this
                            Last edited by Mcgyver; 06-07-2011, 09:02 PM.


                            • #15
                              Anyone got some insight on a good propane torch with a single strait blue flame?
                              I have all three of these, so in my opinion at least here's my list of good, better, and best when it comes to propane torches.

                              First off is the ubiquitous standard brass type that everyone has or has had. I have done a lot of copper tube soldering with this type but I was always wanting more heat, more quickly. It will do but they are sloow, especially when the fittings or junctions get big.

                              Next up is this type, and remember I'm using Bernzomatic just as an example, there other brands but these can be found just about everywhere.
                              This type is head and shoulders above the first one I linked to, way hotter and much quicker. I use this one the most because like a shirt pocket it's handy and always there.

                              I also have an air/propane torch from Goss like this last example. These are very nice if you don't have access to a small acetylene tank. They are very nice to use and because you are not carrying your fuel source with the torch itself, they can get into tight areas easily without feeling cumbersome.

                              But at this price level you may as well opt for the air/acetylene torches as the price is the same. Like Boucher said, the air/acetylene are definitely the way to go if you are going to do this a lot. The air/propane torch is almost as good though, but it has the advantage of using propane, at the cost of not being quite as hot.
                              Home, down in the valley behind the Red Angus
                              Bad Decisions Make Good Stories​