Soldering Help

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jadnashua

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Any new skill can be intimidating to get started with, especially if failure can lead to damage to your home! But, like anything, a little practice and knowledge helps.

Soldering isn't any different. Three basic rules should help get you started along with some practice:
1. Make the pipe AND the inside of the fitting nice and bright clean...do NOT touch those areas with your fingers or hands after cleaning, as that can add some oil that can contaminate it during the soldering process.
2. Add flux to both the pipe AND the inside of the fitting. Flux helps to keep oxygen away from the surface so it doesn't oxidize, which can contaminate the joint, and helps the solder flow.
3. Make sure the joint is dry. Moisture will do a couple of bad things. It will keep the area at the boiling point, which isn't hot enough for solder to melt, and, can build up steam pressure so that it can blow through the joint, leaving a hollow trail, letting it leak.

To add a few more things:
- you want to heat the fitting more than the pipe or just the junction, and you want to move the flame all around the joint to apply heat evenly. The solder will tend to flow towards the heated area, and you want it to penetrate all the way in the full length of the fitting, so heating the fitting is important. Heating the pipe doesn't hurt, but if you only did that, by the time the further end of the fitting was hot, you may have burned out the flux where you had the torch.
- if you overheat the joint, you will burn out the flux, and the joint will likely leak. Especially for someone just starting, I find it works best to use a tinning flux. This is one that has powdered solder mixed in it. When you're heating the joint, once you see that start to melt, you know it will then melt the solder you need to add to finish the joint up. If you've properly heated the pipe and fitting, solder will wick up into a joint on the vertical.
- a good gauge of how much solder to apply is about the length of the diameter of the pipe.
- while the joint is still hot before you add the solder a quick wipe with a cotton rag will remove any excess flux. Then add the solder. The solder will flow because of the heat and the flux.
- make sure that the pipe and fitting won't move while the solder is still molten
- make sure that there is an opening in the pipe (i.e., a valve or something open) to allow any steam that may be generated or gasses to escape easily
- remove the cartridge, O-rings, or any washers from valves prior to heating the valve for soldering
- molten solder can make a nasty burn...it's a good idea to wear gloves and have eye protection. A long-sleeved shirt and pants doesn't hurt, either, and sandals may not be a great idea!
- dealing with a flame, if soldering around flammable materials, you want to have a spray bottle with water in it, and maybe a fire extinguisher available. If necessary, you will want to have a solder shield to protect non-movable flammable materials...a tin can cut and flattened can work, or you can buy one. Spray the area to dampen say the studs, or whatever, first (without getting the pipe and fitting wet!) if it's at risk. Don't burn your house down in the process...an ember can stick around for awhile and start up later.
- buy some extra fittings and pipe and practice! That cost will be less than what you'd pay someone to come and do a small job. Now, a pro will do it faster, but not necessarily better, and time is money, even when you're doing it yourself, so at some point, having a pro do it makes a lot of sense, as may if the work is going to be covered up, and it's difficult to test it prior to that happening...wouldn't want to tear out the new tiled work to fix a leak, so pressure test it first!
- if you DO end up burning the flux, or, during a pressure test, you find it leaks, you CANNOT just add more solder to the joint and expect it to fix it. Once water has gotten to a joint and it leaks, you MUST take the joint apart, thoroughly clean everything up again, and then redo it. If you clean, wipe, and knock the solder off well enough, you can reuse the fitting. Depending on where it is, you might want to replace the fitting as that's the harder thing to clean out enough so it will still fit over the pipe to try again.
- you may get into a situation where you cannot conveniently reach the joint to properly solder it. There are special tools to heat a joint that don't require a torch, but not something the average homeowner will buy. In that situation, you might just break down and use something like a Sharkbite fitting, since it does not use any solder to make the connection. Doing it except under certain special circumstances can cost a whole bunch, and if you don't prep the pipe properly, you can ruin the fitting when installing it. Often, the job relies on the joint being rigid, but a Sharkbite joint will allow the pipe to rotate, so keep that in mind, too about where it may work well. I live in a string of condos, where each unit has an individual shutoff, but the main line is like 2". I needed to replace my main shutoff as it no longer provided a good seal. While I could get to the main building shutoff, doing that meant shutting water off to 9 other units, plus, once it was off, draining enough out of all units so the flow would stop would have been an issue. There are tricks to stop the water flow, but there would be a fair amount of pressure from all of that water up two flights of 10-units...I ended up using a Sharkbite fitting to a valve so I could have the water turned back on in a few minutes rather than waiting forever for things to drain. A Jetswet tool could be a lifesaver, but for a one-time use, not particularly cost-effective.


or the Wassi II unit that comes with multiple pipe size adapter


There are special tools that can add a new valve in line without shutting the water off, and you can try packing in some bread or they make tablets designed to temporarily plug the line to stop the water, but that may be less than satisfactory when there's still a fair amount of volume of water trying to drain out. I had one other situation where I couldn't really get a torch all around the fitting. It was behind a 60-gallon water heater. Moving the WH would have required remaking numerous joints. I ended up using a Sharkbite slip coupling there. So, while there are special tools and ways around most inconvenient situations to get the job done, sometimes, using a special joint like a Sharkbite is the fastest and easiest. I would not use them except in those situations as they can be 10x more expensive per joint. They seal with an O-ring, and if you haven't cleaned up the ends of the pipes, you can damage that when pushing it on. Just like most things...you need to understand and adhere to the 'rules of the game' to make things work.

So, don't be afraid of learning a new skill, but you do need to know the basics and PRACTICE a bit on something less critical. Or, if you've got a friend that has some experience at it, have him/her tutor you and watch over your first few. Don't be afraid and call in a pro...sometimes, that's the best choice. Only you know your limitations, and even with insurance, a failed joint can cost way more than the plumber would have, not counting the inconvenience of getting things fixed after the failure or losing something that can't be replaced in the process. There's a reason why plumbers must apprentice for awhile, and take a test to get a license...they need to practice, too!

(Updated based on comment below...thanks for the help!)
 
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James Henry

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while the joint is still hot and the solder molten, a quick wipe with a cotton rag will make it look better, and help wipe away any excess solder and flux.

Don't do that, you will smear the solder all around the pipe and it will look like crap. Wear cotton gloves. After the flux starts to liquify from applying heat wipe the excess flux off the pipe and fitting with a rag before you apply solder, solder will follow the flux wherever it goes, including on the outside of the pipe.
I can solder a 2" or 3"copper fitting on the vertical without any solder running down the pipe just by wiping off the excess flux that runs down the pipe first.
The other thing most plumbers do is apply solder to the top of the fitting and let it run down which is wrong, heat rises and when you apply solder to the top of the fitting and then apply heat to the bottom of the fitting in preparation to apply solder the solder you applied on top will reheat and fall to the bottom of the fitting. always apply solder to the bottom of a fitting first then finish off on top.
After the joint has been soldered and the solder joint goes from shinny to dull then its safe to wipe the joint down. wipe the joint down vigorously.
 

jadnashua

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Thanks for that...the difference between an occasional user and someone with lots of experience! Always open to refining and improving. Spent time as a certified electronic tech on missiles, radars, etc...do my own plumbing when it's reasonable, but hire a pro when it's not. The skills are similar, but not the same.

The three biggest things though, are clean things well, use flux, and heat all around the fitting.

I updated the original post per the comments...thanks again.
 
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James Henry

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Thanks for that...the difference between an occasional user and someone with lots of experience! Always open to refining and improving. Spent time as a certified electronic tech on missiles, radars, etc...do my own plumbing when it's reasonable, but hire a pro when it's not. The skills are similar, but not the same.

The three biggest things though, are clean things well, use flux, and heat all around the fitting.

I updated the original post per the comments...thanks again.

Your very welcome, hope I didn't come off rude. I get that a lot.
 

jadnashua

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My ego isn't big enough to not recognize when I'm not right...it's just that it doesn't happen all that often! FWIW, when I have had work done, the guys usually wipe after adding the solder...so, parroting what I saw. Your solution seems both logical and next time, I'll try it out for myself. I'm not a fan of big drips or runs, but a smooth coat of solder doesn't bother me unless it's in a highly visible area.
 

Terry

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There are many ways to do things. I was taught to work the bottom joint first and then the top, heat rises.
And then I tried solder at the top first, and then the bottom, Fewer leaks. I went eight months without a leak when I was only doing copper all day long with a journeyman handling the waste and vents. New construction and I can't even begin to tell you how much copper I was throwing in.
I prefer a damp rag for wiping joints. I even hit the joint with a fine water spray when I'm in a hurry, but not right away. I don't like to cool it too fast.
I do like to cool it though. I have plenty of burns on my arms from being there too quickly.

Going to 95/5 in the 70's was a hit with me, because asking the framers to stop pounding hammers wasn't working. The bigger portion of tin helped with that. Fewer leaks on the bigger mult-family jobs. When I mentioned it to the other plumbers, they would also start sneaking the 95/5 into their vans out of the shop.
 

Tuttles Revenge

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There are special tools that can add a new valve in line without shutting the water off, and you can try packing in some bread or they make tablets designed to temporarily plug the line to stop the water, but that may be less than satisfactory when there's still a fair amount of volume of water trying to drain out.

I have a tool that creates dry ice in plastic cuffs that get placed onto pipe that then freezes the water inside the pipe effectively blocking the flow of water to allow work on plumbing systems without shutting off the main water. Doing that in the 30th floor penthouse was the scariest thing I've ever done in my plumbing career.
 

jadnashua

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Neat! There are likely all sorts of specialists tools the average person isn't familiar with, or generally have access to...some, I'm sure are expensive and may take some additional skills to use properly which is why a pro can be handy for some jobs that otherwise would be much more complex or impossible in those specific circumstances. Some might be available at a tool rental, but then you have your time to pick it up, take it back, and the rental costs, which may make the pro with the tool cheaper, and almost certainly faster!
 
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