Proper way to sweat copper pipes?

[Razl]

Let me start by saying I've found plenty of websites with detailed steps and even a video or two on how to properly solder copper pipes.

However, I didn't find one that addressed sweating multiple connections. For example, I tried soldering a T-fitting the other day and didn't know if I should solder all three joints at once or should I do one joint, let it cool, clean the next joint, add flux and reheat with my propane torch?

If I don't do all 3 ends of the T-fitting at once, won't they come undone when I reheat the fitting? I tired doing all three in a row, but ended up burning off all the flux about time I got to the 3rd connection. Any help would be appreciated.

 

[TooManyWheels]

I am not a pro plumber and can not completely visualize your problem, but I have done a lot of soldering.

Clean all the joints before hand, but do not add flux until you actually get around to soldering the joint. I'm not sure it is necessary to let the previous joint cool before doing the next one, unless you see the solder flowing out of the previous joint. If that is the case, and letting the previous joint cool first does not solve the problem, you might want to add a heatsink (a clamp, or vicegrip) to the previous joint to keep that solder from melting. Solder flows toward heat, so consider heating the fitting itself as opposed to the tubes, if you are not already doing so.

 

[oldman]

http://www.copper.org/copperhome/DIY/doityourself_solderingschool.html

This is a good explanation. One tip is to apply the heat to the fitting not on the joint. Most of the time I try to use too much heat and try to rush. Take your time and it will work.

 

[1 FMF]

quote:

---

Originally posted by Razl:
If I don't do all 3 ends of the T-fitting at once, won't they come undone when I reheat the fitting?

---

only if there's force on the pipe which is pulling it out of the T fitting. Otherwise the solder will liquify then resolidify when you heat the copper. That won't hurt anything. Just do whatever is easiest. The most important part of sweating pipe, along with soldering, brazing, and welding of any other material is the preparation and planning. Prep the parts, know how you want to solder them and in which order, get in the most comfortable position as possible so you're not struggling to apply heat at the proper point and so you can get solder applied evenly. After heating the copper, it should only take you 1-2 seconds at most to get solder in the joint, so to do all three sides of the T should not be a problem.
Prior planning prevents p1ss poor performance

 

[kenw]

I just do them pretty much all at once. If you have the correct amount of solder, even it it reflows it won't hurt the joint. Capillary action will keep the solder in place unless you overheat it.

Apply the heat to the pipe, not the T. Start and finish with the end outlets, the base of the T is done 2nd. When you finish a joint, wrap the pipe (not the T) with a wet cloth to heatsink it.