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Red Squirrel 01-29-2013 07:52 PM

Is it fairly easy to sweat copper if never done it before?
I bought the supplies I need. Torch, flux, solder, wire brush, sand paper and flint. Never done this before but I'm about to conquer a few projects. First one is simple, I just want to cut a piece of line that has been capped, and recap it further down.

I've read a few tutorials online and it seems fairly straightforward. Clean the fittings, use wirebrush to rough them up, apply flux, dry fit, heat the fitting, remove flame, apply solder, if it does not melt right away it needs to be heated more. Once it does melt, just follow the outline of the fitting and solder is sucked in then let it dry and wipe down excess and turn on water.

Now is this one of those things it works, or it does not, or could it hold for a while, then randomly burst when I'm not home? That's really my main fear when working with high pressure applications.

What is the best way to test that I did a good job and it will last? I'm thinking I could simply cause lot of water hammer by turning a faucet on/off very fast and if it holds, then I'm good right?

best handyman 01-29-2013 08:09 PM

It not that easy to solder. What are you going to do when there is water in the line. ( Blowing off) what did you tutorials online say to do. Test by turning a faucet on and off is not going to do anything at all.

TheEplumber 01-29-2013 08:12 PM

199 Attachment(s)
You pretty much got it.
The best way to learn is to have some one help you- kind of like teaching your kid to drive- a coach so to say. Watch some you tube videos. You'll see a pattern of crucial steps in most of them that are consistent. Master those steps and your good to go.
Practice at your work bench first. Wasting $10.00 on material is better then drying out carpet :)
Oh, and the least bit of water in the pipes really sucks! A few drops turns to steam and it will escape out the fitting as you heat it- not allowing the solder to suck in. Makes for small pinholes- not fun:no:

Hardway 01-29-2013 08:15 PM


Originally Posted by best handyman (Post 1105222)
It not that easy to solder. What are you going to do when there is water in the line. ( Blowing off) what did you tutorials online say to do. Test by turning a faucet on and off is not going to do anything at all.

What do you do if there is water in the line?

digitalplumber 01-29-2013 08:18 PM

I just finished doing a bathroom. First time. It takes a while to get it down but definitely doable. Key is the heat and not burning the flux, by heating to long.

Get a pair of good heat resistant gloves and learn how to wipe the joint to make it look great.

I had one fitting, that I forgot to solder! And turned on the water! Boy was I thankful insulation was on the wall.

Watch a lot of you tube videos, then go after it. If you are a decent do it your selfer, you can do this. I did not like the water based flux.

ddawg16 01-29-2013 08:20 PM

Eplumber spelled it out pretty good.

A few more notes.....

When you think it's clean....brush it some more. What has worked well for me...if the copper is old (patena on it), I use 200 grit sand paper to get the first layer off....then a 3 M scratch pad....and then the wire brush that you rotate around the pipe....

Make sure you debur the insides of the pipe....that sharp edeg that the pipe cutter creates is a major source of noise when water is flowing.

Make sure the fit is snug but not tight....if you have to force the pieces's too tight.

Flux on both parts.

I apply heat to the heavier part's sucking up most of the heat anyway....then I move to the seam between them...

When you apply the know it's hot enough when it 'sucks' up the solder....I typically apply the solder to the back's coldest part....if it sucks it up there...your hot enough.

Like eplumber said....practice.

Good luck

BigJim 01-29-2013 08:27 PM

This what I have been doing all day today. One thing I do when I turn the water off is to go outside and open an outside faucet because they are usually the lowest and will drain most of the water out. When you get to the faucet you are going to replace open that faucet up and it will usually suck all the water out.

I clean the pipe, then inside the fitting, then rough both of them up. Flux inside fitting and the pipe also, then, well you know the rest.

If you are emptying your water heater be sure to turn it off, it could burn it up if it gets empty.

jagans 01-29-2013 08:47 PM

you should not use sandpaper. You should use plumbers emory.

I always use tinning flux mixed with regular flux. Do not use excessive heat, and keep the heat on the fitting, never on the solder or flux itself. I have a torch that puts out three small pencil flames, I like it a lot. Once you see the tinning flux tin off you follow around with solid wire solder, and you will see it get sucked right in through capillary action. A good solder joint will leave a small drip on the collar of the fitting. Let it cool naturally.

One main point is clean. It has to be bright cleaned, then fluxed right away.

I clamp everything in place, then sweat them all at once. A trick an old timer taught me is to tap the collars of fittings so you make them minutely out of round. This way they won't drop when you sweat if you have a horizontal pipe to an El to a stub out.

Practice and post your work first before firing for effect.

Red Squirrel 01-29-2013 08:48 PM

Actually this pipe will be one of the lowest parts in the house (it's in the basement) but I think it's still higher than the shut off valve which has a little plug so I will probably be ok if I just open that, and open a tap uptstairs for venting. That's another thing too, the little drain plug on my main valve is leaking. I'll have to call the city and see what is involved in changing that. I don't think I'm allowed to touch the main shut off outside.

Also kinda a side question, but what is an NTP fitting? Is that something I could easily find a female for at the hardware store? Is it the same thread that is used on many fittings like valves, water heater and such? (not to be confused with the end that a hose can attach to) I want to install a pressure gauge on my main as well as a regulator (before the gauge) so I can adjust the pressure. I suspect it is way too high. They do make "test" gauges that connect on a faucet, but I kind of like the idea of having one built in. They all seem to have an NTP fitting so I want to make sure it's something I can easily get. Something like this:

So really think what I will do is buy some pipe and fittings and practice first. I can then hook up my test contraption to the faucet and apply full pressure and see if it holds.

Edit: and yeah I can post it first too. I'm tempted to do this NOW, but too bad everything is closed. :P Tomorrow is another day.

Javiles 01-29-2013 08:56 PM

if your capping off a line and you have limited experience i recommend that at the end of the pipe you sweat a male or female adapter then after you have soldered the fitting screw the cap or plug on with pipe dope, you'll thank me later. :yes:

TheEplumber 01-29-2013 08:56 PM

199 Attachment(s)
Good luck with the soldering- sounds like a bad spot to me.
Once you've drained out the water- close the faucets. This will air lock the system and keep most of the pocketed water from coming out while soldering.
If it doesn't go well you could always put a shakebite cap on it and tackle it later.
You can buy 1/2x1/4 copper sweat x thread bushing- put it in a tee on you main and screw a gauge into it- assuming you have a copper main

jeffnc 01-29-2013 09:06 PM


Originally Posted by TheEplumber (Post 1105224)
Practice at your work bench first.

That's the main thing.

Or forget all this nonsense and do it in PEX instead.

funfool 01-29-2013 09:19 PM

lowest part in the house always skeers me.
You can turn it off at the street, you can open all the faucets, may actually need to drain the water heater.
If you are in the lowest part of the house, and you see drips of water or is dry then all of a sudden a drip comes down the line, this will kill your solder joint. Simply the steam will kill the solder.

I just recently ran into this issue for the 100nth time.
Lucky for me, the old widow next door asked if I could help her remove her curtains the day before. She wanted to have them dry cleaned, so at the end of day I took my step ladder over and helped her. She said if I ever wanted a bottle of water or something, to ask.

So next day on the job and cant get water to quit dripping, I went to the old lady next door and asked for a piece of bread, she had some stale bread and I stuffed the copper pipes full of it, did my solder and it all came out fine.
The bread soaks up the water before it gets to the joints, when you turn water on it turns to mush and gets flushed out.

Is easy to solder, sometimes you need tricks or old lady next door.

funfool 01-29-2013 09:20 PM

and yeah I would switch to pex every chance I get.

Red Squirrel 01-29-2013 10:20 PM

Actually switching it all to pex is an option too... Lot of these pipes are really old, perhaps original to the house, and some are in the way if I want to frame that wall. I still have the electrical panel to worry about though... but if I can get the pipes out of the way it's a start. For the panel the feeder might have enough slack to just bring the cut off switch ahead a few inches. Hmm, this might turn into a bigger job but be worth it in the end.

I might still attempt to cap it first though but I'll definitely practice then pressure test my practice setup. My fear is just that if I don't do a good enough job it could burst when I'm not home or something.

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