Sweating copper.

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Chris

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What tips or tricks can you give for the average guy about sweating copper. I have noticed that most will not attempt to do a job because of this.
 
Piece of cake. I'm more afraid of digging the ditch than sweating copper :D

Clean the pipe and fittings thoroughly with emery cloth on the pipe, brush the fitting, slather some flux on the inside of the female and outside of the male, connect, heat, apply solder.

In 99% of residential pipe sizes, heat only needs to be applied to one side of the pipe. Heat rises, so point the torch at the bottom side of the connection.

Apply the solder to the opposite side of the heated side. the solder will "pull" its way around and seal the fitting.

Wipe excess flux and move to the next one.

Mapp gas is preferred.

http://i.ehow.com/images/GlobalPhoto/Articles/5495871/IMGA0652-main_Full.jpg
 
Not for residential plumbing.
Some brazing for under ground plumbing and med gas lines.
 
The solder will flow to the heat. After cleaning and adding flux to the joints, I heat the fitting where I want the solder to go to. Wiping the joint immediately after adding the solder serves tthree purposes. It will fill in any pinholes in the solder at the fitting cup, it will remove the excess flux and prevent green colored joints later and it makes the joint look professional.
 
Dont forget to use lead free solder and flush all the pipes out before anyone gets a drink. Also, If you do get a leak you will need to get all the water out of that pipe to re-solder it.
 
The solder will flow to the heat. After cleaning and adding flux to the joints, I heat the fitting where I want the solder to go to. Wiping the joint immediately after adding the solder serves tthree purposes.
So do you wipe before the solder solidifies or after? I am always afraid of getting a "cold joint" and leakage if I wipe it too soon. :confused:
 
The rag or gloved finger I use to wipe the joint is going towards the joint as I remove the heat. I wipe while the solder is still a liquid.
 
OH! So are you using a dry rag/glove then? I have always heard / read to use a wet rag. Is that wrong? :confused:
 
No it's not wrong. Some rags have a high polyester content and wil melt on contact. All cotton rags are hard to come by anymore. A moist rag, not dripping wet, wil do just fine. Be careful of steam burns.

I have used silver bearing solder in the past, is that acceptable for potable water systems?
 
A wet rag will "set" the solder immediately. I always wear cotton jersey gloves when soldering and do nicely for wiping a joint. I go back a few minutes later with a wet rag to remove the melted flux.
 
OK, that is what I was getting at. I've wiped joints before with a "moist" rag too soon, and the solder 'curdled' in the connection from cooling too fast and they leaked. The dry wipe first, followed by the wet later makes sense to me.

Thanks for the lesson! :)
 
If you have cleaned the pipe and the fitting properly, only a small amount of flux is needed, just enough to coat the surface. Excess flux runs down both the inside and outside of the pipe, making a mess. And definitely, wipe the flux off after the joint has cooled. Green pipe looks like crap.
 
no,its not wrong.you could use a wet rag or a dry one. see, were plumbers and we take pride in our work. not only do we need our work to be leak free, we need it to look good to. good luck
 
i have all of my valves open one main level and upstairs, and the main is off. I am still getting some drpis at my repair area in the basement,and I am unable toseat the copper lines. Any tips on what to do?
 
If it is just a slight drip, get everything ready, then push some bread down the pipe. Finish assembling the last joint, then sweat it.
The bread will soak up water and will hold it back unless pressure builds up behind it. Also, it breaks down and will not plug up valves.

Do make sure to take the aerator off of all your faucets and flush those out, as the fine mesh in the aerators can clog up.
 
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