How to Solder a Proper Plumbing Connection





Introduction: How to Solder a Proper Plumbing Connection

About: I was recently introduced to the beautiful world of making and have been hooked ever since!

In all areas of plumbing, it is very important to solder a good, clean joint. If you don't, there can be leaks of gases or liquids that flow through the pipe. So, in this instructable, I look forward to teaching you just that.

Step 1: What Do You Need to Solder a Proper Connection?

Things You Need

1. Flux Paste

2. Solder (Lead-Free)

3. Steel Wool

Note 1: When you use the steel wool it is advised to wear gloves as to not get any metal bits stuck in your hand. You also need these because the propane torch is very hot and so is the piping after you heat it up.

Note 2: As seen in one of the pictures above, something that you can do is use a Car Battery Terminal Brush to make it a lot easier when scratching up the inside of the pipe that you want to use. In the comments below OmarJ3 also supplied information that when you go back to solder past works you can get one of these with a stem to make it easier to clean the pipe.

4. Sparker

5. Rag

6. The pipes that you are soldering


1. Propane Torch

2. Safety Glasses

3. Thick Work Gloves

Step 2: Prepping the Pipe

Prepping the pipe not only makes the pipe easier to solder but also helps the pipes hold together better by itself. To do this you must know that there are two different parts if a pipe. There is a fitting, and then there are the pipes themselves. The connectors are the larger bit of piping that the pipe fits into. For the fittings, you should use some steel wool to scratch up the inside (or you can use the car battery terminal brush as advised earlier). Then, use the steel wool again to scratch up the outside of the pipe. Finally, apply only a little bit of the flux paste to the end of the pipe. Connect fitting and pipe.

Note: In the comments below it was advised by tytower to only apply the flux paste where you want the solder to go. This is because the solder will go everywhere there is flux paste is. Thank you tytowers for commenting about this very helpful tip!

Step 3: Soldering the Joint

So, once you have prepped the pipe, you are ready to solder. Turn the propane torch on, using the sparker to ignite the flame. Then, put the tip of the flame on the fitting and put it no closer. If you do, it will basically turn the flux paste to ash, and you need the flux paste to conduct the heat. Once the pipe looks hot enough (this can be determined by seeing if the pipe starts to discolor), put your solder up against the joint (the joint is the place where the pipe and fittings meet). If the solder melts, take the torch away from the piping and let the solder ease into the joint, all the way around. You do not need a lot of solder, so don't use too much. However, if you see a lot of excess solder that has formed, quickly wipe it with a damp rag before it hardens.

Note 1: In the comments below OmarJ3 supplied the helpful information that before soldering pipes together that have already had water flowing through them, make sure that all of the water is out. The heat will be sucked in by the water, not the piping. Also, referring to the same thing mtoddh recommended below too, in case there is a leak shove a piece of bread into the piping to stop it. When you turn the water back on it will dissolve and flush out the bread. Of course, it was also said by DaFoxx50 to make sure to use white bread, because whole grain won't dissolve. Very important. It would be very embarrassing to get all that way and to have piece of bread be your downfall.

Note 2: In the comments below dlemke advised that you should heat the fitting from the bottom, and the heat will spread to the top. Then, because solder jumps to the heat, put the solder on the top and it will spread downwards.

Step 4: Cleaning Your Joints

So, when you are done you will see that the heat has probably messed up the coloring and dirtied some of the piping exposed to the flame (as seen above). When the piping has cooled, use the steel wool you used earlier to rub that off until the pipe looks as it did. You can get a lot of the messy stuff off but if there is any access, solder that has hardened, you are just going to have to leave it unless you want to heat the solder up again and wipe it off with a damp rag. However, if you do this if too much solder melts off you may need to apply more.

Note: It was advised by cdays_01 that after you are finished to add a little bit of flux paste to the metal and wipe it off to better clean it. However, if you remember, you could just brush it off with your finger while it's molten (you're wearing a glove).

Step 5: Step Back and Admire Your Work

Thanks for reading my Instructable. Also, a shout out to my Dad is in order as he is the person that passed all of this useful information onto me, and worked with me until I fully understood the essentials of soldering. Also, thank you for all of the extremely helpful comments that people have left me below. It really makes me happy and interested to hear all of your tips! Please remember to favorite and follow!



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    Having a sink that is working properly is one of those essential things we forget about until we don't have one. Sometimes hair, grease, and other debris build up in your pipes causing your sink to drain slowly or stop up entirely. You should try doing trenchless piping from one of these service providers,, mrrooter, etc. it might clean up all your drain issues. Also any other plumbing problems, if any, would also be solved with this.

    Next step graduate to oxy accetylene torch and silver solder for a really reliable joint . Soft solder tends to not flow properly due to uneven heat in some areas leading to leaks in use.

    13 replies

    Tytower, if you prep the copper first, paste the tube & the fitting both, heat the joint with propane torch, add solder the joint will hold pressure. The only time oxy accetylene & silver solder is used is when you are working on refridgerant lines. Silver solder is rarely used on city water. If you have to go back & work on it again, dealing with silver solder is a pain. If you don't know silver solder was used, heating with a propane torch won't get you anywhere, as propane won't get the solder hot enough to remove the fitting

    Just remember its a big world . here in australia we use it all the time and it is reliable . You don't go back because it does not leak or let go with vibration . Thats the point you have missed.

    Not many common areas have the need for silver solder joint. It is expensive and a lot harder to learn. You also will need a hotter heat source and silver solder paste.. No, I am not talking about brazing with rods that have a small percentage of silver. I have usually only found silver solder joints on high end govt. projects.

    Paste wise, no. You can use the same paste as you do with regular solder. You just need to use sil-fos as well.

    Well sil-flos might not require paste, but we always used it. For a few reasons, if you use it you don't have to worry about the Tube gualding in the fitting before it is set in the direction you want it to go. Cause sometimes the fittings did that. And also the paste kept the tube & the fitting shiney after you cleaned it. We used it all the time, worked better then the liquid crap.

    Sil-Fos requires no flux. Sil-Fos is a brand name of brazing rod that is used in the refrigeration trade and has different amounts of silver from 7.5-35%. Using real silver requires it's own flux or paste as it is called. Regular solder whether it has lead or not, uses it's own type of flux. Silver based brazing rods are very expensive, so you can imagine what it would cost to use real silver solder joints on any project. The only example I can think of to use pure silver joints, off the top of my head is where you need to go from a ferrous metal to a non-ferrous metal.

    Just for information purposes, refrigeration copper is not the same as plumbing copper. It is not only measured differently, it is manufactured differently to make sure there is no oils in the pipe left from the process that would mess with refrigeration oil.

    Sil-fos™ is a silver-copper-phosphorus brazing filler metal, which is used to braze copper and copper alloys. When brazing copper, the phosphorus within the alloy imparts a metallurgical based self-fluxing capability.

    Swiped this from a search engine to make it clearer.

    Silver solder joints are the plumbers preference in Australia . Perhaps
    you do not have the temperatures and pressures we have . You are very
    contradictory . I usually find that such all encompassing statements are made by people
    who really have very little practical experience.

    I have a lot of experience soldering, brazing, and yes, even silver solder joints. The only place I can think of where I have to use actual silver solder is on joints that go from ferrous to nonferrous metals. More precisely, on compressors that have a steel outlet tube that has the copper plate burned off by someone getting it too hot. Manufacturers plate the outlet tubes with a thin layer of copper to allow the transition from steel to copper without using the more expensive silver. The copper plating on the steel tube is very thin and this can be damaged by using too much heat. Silver solder, which is very expensive and hard to find at most supply stores, can be used to do these repairs.

    Through the years in the HAVC field, we have seen joints go from lead solder to self-piercing couplings, to silver content brazing rods. Brazing is much more durable and contains no lead, but the newer lead free solder requires less heat and is easier to use on water pipes. The cost is probably the main reason solder is used over brazing even with experienced plumbers.

    I believe a lot of people confuse silver solder joints with brazing using brazing rods that contain varying amounts of silver. This is not a true "silver solder" joint. There are definitely some legitimate uses for silver solder joints, but not in general domestic plumbing.

    My comments were merely meant to be informative. I did not want to offend anyone, and I hope you were not offended. It is easy to come off abrasive when making comments in a comment section. I probably need to edit myself more often.

    Most plumbers in the US don't have or use oxy acetylene rigs.

    In many areas, especially in the United States, Soft solder is the only legal solder for sweated connections per building codes, though below slabs (for repairs only), brazing with an appropriate brass alloy is required

    That's precisely what defines a proper plumbing connection - if you heat it unevenly, without sufficient flame power, you get crappy joints. Care and experience delivers perfect joints every time.

    Nix to the steel wool for cleaning the tube. Use sand cloth instead. Much easier to use and easier to clean the tube of sand instead of the steel wool particles. To clean the fitting use the proper sized fitting brush. So much easier to use & much faster. After both tube & fitting is cleaned, use nokorode paste on both, join them together, heat, solder, wipe with a rag, go to the next joint & do the same.

    Good work, ShadowRoch. It's especially impressive that when others
    offered suggestions or corrections, you didn't adopt the attitude of "I
    already know it all." I have three graduate degrees in two different
    fields, and I don't "know it all" about either of them, far from it.

    have one comment; the last picture shows you kneeling by your work; I
    assume the picture was posed to serve as a conclusion. But you're posing
    without the safety glasses you quite correctly recommend. You should be
    shown doing what you say. That said, I look forward to your next Instructable!

    2 replies

    Without too many words, "I know one thing: that I know nothing" [Socrates]

    Thank you. I really love to learn and really thank you for that compliment. It is one that really makes me feel happy. I do think people should be shown doing what they say, however, I am actually wearing glasses in the picture, you just have to look closely.

    This process can be frustrating when any part of the procedure is neglected. It used to be much easier when there was some lead content in the solder. Also, note that in existing circuits, any residual water must be drained, as it will absorb too much heat, and prevent flow of the solder. Also, one can buy a battery terminal brush with a "stem" that will scrub the insides of the fittings. This is important when re-using old fittings, or if the joint needs to be redone after a failed attempt.