Quick question about copper pipe soldering

[Eigenvector]

So far my efforts are working out learning how to do this, but I have a couple of questions

I'm heating up the fitting and the flame on my torch turns green. I say "Okay it's time to apply the solder" so I'm finding that I can't make it around the entire circumference of the joint without reheating. Is that normal or am I soldering too early?

Also, when torching a 1/2" fitting, I'm moving the flame around the heat the fitting evenly - is that really necessary?

Anyways I don't need a primer on how to solder, there's plenty of resources out there for that. But I just had a couple of questions about what I'm seeing.

[Jeff]

Usually if you see much green the copper is too hot. Even heating is important. I just gently tap the joint with the solder until you feel/see it melt, heat just a little more, then push the solder onto the joint. If the surfaces are clean and well fluxed the solder should quickly flow into and around the joint. Don't pile excess solder on, always a sign of unprofessional work.

[Eigenvector]

Well I'm all about unprofessional. However I do have about 10 elbows and T's to practice with.

I take it that heating doesn't take long at all. I'm seeing a green flame after about 10 to 20 seconds.

[Sacramento Dave]

Seeing green has nothing to do with the coppers heat, that's the gas your using. Hear is what you want to do heat the pipe evenly make sure you go a couple inches each side of the fitting your soldiering. When the solider starts to flow put the heat on the back of the fitting the heat draws the solider in. I also like to feed the solider in on the top side most leaks seem to be on the top so this helps. Most the time with 3/4" and 1/2" it doesn't make that big of a deference but it's a good practice. In time you will learn to pull your torch back to control the heat. I also would recommend no-corrode ( brand) flux. Some people don't even sand the pipe or fittings before soldering I always do I think it makes for a better job.Once you solider your joint/joints let the cool if you bump it or wipe the joint to soon while the solider is still molten you will have a leak for sure. Just take your time it's not Rocket science.

"Jeff" wrote in message news:vWpEh.61464$ [e-mail]...

[Ken]

For what it is worth, I too struggled with my soldering technique with respect to copper tubing. The tip that helped the most for me was to watch the bubbling of the flux. When it stopped, it was time to put the solder on it, and remove the heat. Over heating causes the solder to bubble out rather than flow. Practice is the best way to prepare for a job. Good luck.

[Oren]

Apply heat on elbows on the outside radius. It will draw flux and solder into the joint.

T's and couplings - heat in the center to have the same.

-- Oren

"Well, it doesn't happen all the time, but when it happens, it happens constantly."

[Steve Barker]

Green flame = too hot too fast. what are you heating with?

[Eigenvector]

I'm using a propane torch. You know, the old Benzomatic

The sources that I've read, and actually there are quite a bit of them, all say that a green flame indicates the joint is ready. It does seem to work that way too, the solder typically doesn't melt until that point is reached. I'm undoubtedly moving too slow when I apply the solder, but green flame seems to be the right point - about the time the flux stops smoking.

[Oren]

Not burning the flux is very, very important.

-- Oren

"Well, it doesn't happen all the time, but when it happens, it happens constantly."

[Eigenvector]

Well that's why I bought lots of fittings - practice practice practice. Any idea how long a bottle of propane lasts?

[Edwin Pawlowski]

Some years ago I worked at a place where they did production soldering of joints. Thousands of joints per day. No one ever used a green flame as a guide.

Nor have I ever seen a Bernzomatic heat up a joint in ten seconds, especially for the lead free solders.

Practice a bit more and heat a bit more.

[Bob]

Which brings up another question(s). HD sells presoldered fittings - the fitting has a ridge filled with solder about 1/4" inside the lip. Anyone have any experience with them? Are these worth the extra 10-15 cents for novice work? Do they have enough solder for a good joint? Can you screw them up by overheating?

Bob

[Sacramento Dave]

Sometimes the flame will change color when you gas is getting low especially with acetylene. I have never heard about a Green flame as an indicator the pipe is ready, but do I know I'm just a plumber.

[Eigenvector]

I intend too. Nothing wrong with practicing, except of course for the money spent.

Not arguing with you, just giving you samples of where I picked up the tip that green flame is an indicator.

As you say, practice practice, practice.

[Eigenvector]

Read my response to Ed, that's where I picked that up.

[BobK207]

EV-

Forget that green flame thing, not a good indication of proper temp

I can tell by how the fitting color changes...too localized color change, not spreading the heat good enough...move the torch around, "paint" the fitting with heat

Do not overheat / burn the flux.

Forget the propane, not enough heat, switch to Mapp Gas (might work with your current BM head)

I used Benzomatic / propane with my dad 40+ years ago.....not enough heat unless you're doing small joints & no wind. About 25 years ago I switched to an air breathing acetylene rig for big / lots of joints; can sweat in a wind storm. :)

For the one off or few joints...Mapp gas...less hassle than dragging out the tank, hose & torch.

cheers Bob

[Eigenvector]

Well for now I'm using it, but not relying on it. It does generally seem to be a decent indicator of when the copper is hot enough, but so far in the tests that I'm done it can mean the joint is TOO hot - in which case the solder beads up and rolls off rather than wicking into the joint.

1 perfect joint, 6 crappy ones, 2 failures.

A second question, is it common for those joints to be very tight when you fit them together? I was wondering if my pipe cutter was flaring the ends and making the joint too tight to fit. On some of them I simply couldn't get them all the way together - not a problem on practice joints but in future I'll want them together obviously.

[BobK207]

EV-

Believe me, the green flame thing is totally bogus indicator.

The copper color change is a better one,

Too hot is bad, you want uniform heat, quickly applied,

don't burn the flux, if you're using a little torch use Mapp

At the correct heat that solder will suck in & you're done in an instant.

Q2....tight is bad!

The tube & the fitting should easily slip together; the fitting should easily spin on the tube.

You want a gap; that's where the solder goes.....about 3 year ago I was sweated a drop ear elbow (1") that was a real tight fit. Too lazy to correct the problem, in a hurry, wanted to be done....... Turned out there was a tiny point of interference between the tube & the fitting.

Sure enough I got a leaker...took it apart, found the interference, filed it off. Re-soldered it, no problem

So a gap everywhere is important...I forget the designed in gap but I sure its in the .002/.003" range.

Too big solder won't fill, no gap...no room for solder.

cheers Bob

[Eigenvector]

Damn, it's gonna take me forever to learn how to do this.

One other thing I learned, don't do this near the smoke alarm - all that smoke from the flux set off the alarm scaring me and not noticing the drop of solder on my knuckle from the joint I was practicing on. At least I had sense not to drop the torch. Damn that hurt.

I appreciate you sticking with me on this. It was a lot easier for me to learn arc welding than soldering for some reason (Engineering degree requires proficiency in this at my Alma Mater). I flunked out of brazing, but passed on welding even with those goofy masks on that you can barely see through even with the arc going. How welders can see what they're doing I'll never know.

[Eigenvector]

Damn, it's gonna take me forever to learn how to do this.

One other thing I learned, don't do this near the smoke alarm - all that smoke from the flux set off the alarm scaring me and not noticing the drop of solder on my knuckle from the joint I was practicing on. At least I had sense not to drop the torch. Damn that hurt.

I appreciate you sticking with me on this. It was a lot easier for me to learn arc welding than soldering for some reason (Engineering degree requires proficiency in this at my Alma Mater). I flunked out of brazing, but passed on welding even with those goofy masks on that you can barely see through even with the arc going. How welders can see what they're doing I'll never know.