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Trouble soldering

2740 Views 18 Replies 9 Participants Last post by  comp1911
I am trying to teach myself to solder...I bought a torch (propylene i think), cutter, some pipes & fittings, flux, solder, etc.

I successfully made some joints, but they were a mess. I have watched a bunch of videos on how to solder, and the people in the videos seem to heat the joint from the bottom, and simply touch the solder at the top, and it flows all the way around, with me, it just seems to flow around 1/3 or so of the joint, and drips. I end up having to run the solder all the way around, and it turns into a big mess.

I am thinking maybe I am putting on the flux wrong, i just coat the inside of the fitting and the outside of the pipe, slide in, give a 1/4 turn, and start heating.

I also cleaned the inside of the fitting with a wire brush and the outside of the pipe with sandpaper before putting the flux on.

Or maybe I am not getting the joint hot enough?

Thanks.
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If you have not done so, you need to read and re-read this thread...its a great primer on "How to Solder Copper"
I read through it, I'll go over it again, thanks.
If you truly beleive you are using good technique, try a different can of flux... there is a post on here somewhere from me last year having a terrible time trying to solder - mind you, I had never had trouble before, I tried everything to fix the problem. Then I think someone suggested getting new flux - I tried that and had zero problems... I then went back to the old flux for a try and had a problem.

That said, if its dripping you are probably using more than needed. Coat Flux evenly. Heat the fitting, not the pipe or the joint. A good trick is to look really closely at the flame, when you start seeing a green hue, its ready. Put a little hook bend in your solder and use it to go around the back to the front. Lots of times, you will have to run the solder around a bit, not just "touch" it to the joint. Have a damp rag nearby for cleanup.. Remember also, clean is not necessarily more functional, if it holds it holds.
It takes practice. It also becomes easier when you are more familiar with your tools. I've used the cheap propane torches like the one you picked up and the MAPP gas torches and acetylene torches and in a pinch I have even used an oxy-acetylene rig to solder pipe. It sounds like you are doing everything correctly, but you just need to gain confidence. Be carefull not to touch the surfaces you want to solder after you sand or wire brush them. Oil and dirt from your fingers will interfere with the flux. The flux is a chemical cleaner that is supposed to condition the surface to be soldered to readily accept the solder, but if you touch the fluxed surface with your fingers (or gloves) you can just about forget about getting a good solder joint. When you solder any copper pipe, one small drop of moisture inside the pipe will prevent the solder from flowing. It will ball up, but it will not flow. Moisture can be flux or water or oil-anything. When you put the torch flame to the joint the tip of the inner flame should just touch the pipe surface and the outer flame will do the preheating and wash the pipe and joint. Just as the flux stops bubbling or boiling off touch the solder to the pipe generally on the side opposite the flame. This is so the pipe is hot enough all the way around; not just where the flame is. Touch the solder to the joint you want to solder not just the pipe and not just the fitting. If the flame is slightly angled or pointed towards the joint from the pipe side the procedure will go much faster. Touch the solder to the joint 2-3 quick times; more heat is not always better; just use enough to get a good flow. When the solder drips off the joint you're done. The joint is full and you can melt down a 1#roll of solder and it won't get any better. Have a wet rag handy to wipe the joint down for a nice finish. AND practice, practice, practice !!!
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Wow, thanks for all the great advice. I am going to buy more fittings and pipe on my way home today, and do a bunch more connections. I want to get much more comfortable before i bring that torch or cutter anywhere near my real water lines.
New dry fittings and pipes are much easier than cutting into an existing water line. Once you do cut into your water line you have to make sure to get the water out. This can be a problem as the lay out of the pipe dose not always allow for easy drainage.
Do the white bread trick to keep water drips out of the joint.
Do the white bread trick to keep water drips out of the joint.


That does work, but only on very, very slow leak/drain. One main source of the leaking water is a leaking gate valve at the meter. If the one prior to the meter slows it down enough, I just disconnect the meter and allow the water to drain into a bucket.
Soldering copper pipes is one of my favorite things to do. It's like magic, and it's easy. If it's not working for you, it is likely that you don't have good flux or your torch isn't hot enough, or....?

You should be able to apply the solder to one part of the joint, and the flux should conduct it into the joint and throughout it. Like I said, it's magic.
Thanks. I had a plumber replace my main valves by my meter about a month ago with new watts ball valves, so luckily I have a good shutoff and can avoid leaks.

I think i wasn't getting the joint hot enough. I just bought the flux and solder, so i doubt it was bad flux...unless the plumbing flux i bought was a bad brand. I don't remember the brand off the top of my head. I didn't mix the flux before applying though, so maybe that was it?

What I'm trying to do is learn to solder so I can branch off my main water line for a sprinkler system, I just got myself a work bench with a vice on it, should make things easier. If I can't teach myself to solder by this summer, then I will just call a plumber! :eek: The thing that makes me nervous about doing this is if I mess up...I have no water in my house till it's fixed. But taking that chance is worth saving the amount the plumber wants.

(I posted another thread about the sprinkler system install here...)
http://www.diychatroom.com/f7/double-check-valve-installation-few-other-questions-42606/
Thanks. I had a plumber replace my main valves by my meter about a month ago with new watts ball valves, so luckily I have a good shutoff and can avoid leaks.

I think i wasn't getting the joint hot enough. I just bought the flux and solder, so i doubt it was bad flux...unless the plumbing flux i bought was a bad brand. I don't remember the brand off the top of my head. I didn't mix the flux before applying though, so maybe that was it?

What I'm trying to do is learn to solder so I can branch off my main water line for a sprinkler system, I just got myself a work bench with a vice on it, should make things easier. If I can't teach myself to solder by this summer, then I will just call a plumber! :eek: The thing that makes me nervous about doing this is if I mess up...I have no water in my house till it's fixed. But taking that chance is worth saving the amount the plumber wants.

(I posted another thread about the sprinkler system install here...)
http://www.diychatroom.com/f7/double-check-valve-installation-few-other-questions-42606/
I've used different fluxes and never really noticed a difference, so I doubt it's that. It's probably a heat issue.

I usually keep my solder pressed to the joint opposite the flame until it melts in. When it happens, it happens in an instant. Once it gets hot, it's done that fast. But the solder has to be in contact with the copper and the flux for it to work. The solder has to get hot, but it should get its heat from the copper.

Some other trouble-shooting ideas:

1) How are you supporting your pipe and joint while you're practicing? If you put them in a vise, the vice will conduct heat away from the pipe.

2) Make sure you're working with a pretty full can of propylene/propane and have the throttle wide open; low pressure will mean low heat.

3) Consider trying a different nozzle/tip. I've got several laying around, and some are definitely better than others.

4) Are you working with 3/4 and 1/2 inch copper? Anything bigger is going to take a lot of heat.

5) How thick is your solder? It shouldn't be thicker than, say, 1/8-inch.
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A lawn sprinkler or fire protection sprinkler?
1. I just had it clamped to a 2x4 that was laying off the edge of a table. I just bought a black and decker workmate (wooden vice type thing). Am I better off wrapping the pipe in a towel or something where the vice squeezes it to insulate it?

2. Brand new propylene tank. I just bought it to replace my propane, so I think it will work better tomorrow.

3. trying tomorrow

4. 3/4" copper pipes, though I'll need to solder 1" for my project.

5. it's standard (i think) plumbing solder, about 1/16th to 1/8th thick.

Thanks.
Try some 1/2-inch to start. I bet it'll work great, and if it does, then you'll know the 3/4 is not getting hot enough, which a different nozzle could fix.
Make sure your heating the fitting not the pipe.
Make sure both fitting and pipe are brushed clean.
If you get the pipe and fitting at the same heat you will have problems.
You can wipe off any excess drip before it cools.
1. I just had it clamped to a 2x4 that was laying off the edge of a table. I just bought a black and decker workmate (wooden vice type thing). Am I better off wrapping the pipe in a towel or something where the vice squeezes it to insulate it?
No, it should be fine as long as the joint your soldering isn't clamped directly in the vise. If the joint is at the end of a few inches of pipe, you should be fine.
A lawn sprinkler or fire protection sprinkler?
Sorry - lawn sprinkler.
clean
clean
clean

tinning flux

MAPP gas

:thumbsup:
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