Looking for good advice on sweating copper (newbie here)

warno

I'm a welder not a sweater(?), I weld pipes nearly everyday. But I have only done a few sweat jobs.

I have a few dissimilar metal joints in my plumbing project that I'm doing at home and I handled them ok at work on the bench. They were copper to stainless, and I used 50% silver solder and high temp Flux. Our inspector at work said they looked really good for my first time doing dissimilar metals. Then I had to do a simple copper to copper joint. I want using a 5% silver with no flux. I wasn't getting it hot enough and got frustrated to the point I asked our copper line lead man for help. He knocked them out no problem.

So that was at work now I have to do my at home portion of the project. Almost all of it is copper to copper with the exception of 7 sweat fitting brass body valves I need to put in. 4 of the valves are mounting vertical and will need the solder to flow up into the joint (not sure of proper terminology). I think I can handle the copper joints for the most part but I'm really worried about burning the seats out of my valves. I have a "cool gel" spray I plan to use but I'm still concerned.

So my question is could anyone point me in the direction of a good advice youtube video or online advice or give any advice that could help me out.

Please and thank you in advance.

hot_rod

Soft solder is what you want to do, under 500° melt point.

I use JW Harris Bridgit.

Here is a video from their site.

Nibco and the copper.org also have soldering videos

Don't over flux, don't overheat, clean fitting and tube with scratch cloth.

http://www.harrisproductsgroup.com/en/Products/Alloys/Soldering/Lead-Free-Solders/Bridgit.aspx

hot_rod

I think this is an example of your weld skill from another site. If that was a water tight weld on first try, you will have no problem soldering once you see the technique.

warno

Yes, that is my project I'm working on. I have no doubt that my welds are water tight as we test are units at work to 300 psi air, but sweating is another story. I haven't posted any pics of my copper to stainless joints but I'm pretty confident in them as well. Thank you for info. The video makes it seem almost too easy. Lol

What is a good technique for doing my valve joints? Any help on those?

warno

I just watched the video from the nibco website. Again these guys make it look too easy. I'll practice on a few junk joints at work before I commit to my own pieces. Thanks for the help.

On a side note could someone explain to me how soldering holds things together so well? Like in the nibco video they show the pieces "peeled" apart. I know from experience you aren't peeling any decent welds apart, do to fushion of materials, with hand tools, so how is it that solder holds a joint together?

rick in Alaska

When I a soldering valves, ball valves that is, I leave them partially open when soldering them. If you try and solder them with the valve closed, they will blow out the seal. The cavity that the ball is in is sealed when it is closed, and the pressure can build up inside it when you heat up the joint, then blow out the seal.
When you are soldering the lower joint on a vertical run, heat the tube a little and then the socket. I try and run the heat around the joint to make it even as possible, and use low heat to keep the flux from burning. Test by touching the solder frequently until it melts. If you have cleaned it good, fluxed it, and didn't burn the flux, the solder should just flow up in to the joint by capillary action. Keep just enough heat on the joint to keep the solder flowing, including taking the torch away as needed so you don't burn it.
If the flame color starts turning green as you are heating, it is too hot and the flux is burning.
After the joint is filled, stop heating and let it cool. After it has cooled a bit and it has gone dull in color, take a damp rag and clean it up to get rid of excess flux.
The joint is held together first by being a tight tolerance fit, and then by the bond from the solder, not by actually "fusing" the two parts together such as in welding.
Hope this helps and makes sense. Been a long day and something tells me I am missing something here.
Oh yeah, I like Bridgett silver bearing solder also. Looks good when done.
Rick

warno

All good info. Thanks guys.

ChrisJ

Not sure if it was mentioned and I missed it, but when soldering ball valves 1/2 open, do not touch them until they cool. Once the valve cools down a good amount you can go ahead and fully open or close them but not before.

I'm not 100% sure that it damages them, but the few times I tried I really didn't like how it felt.

BTW, that weld looks fantastic.

Harvey Ramer

If you are soldering to lead free brass, make sure the brass is extremely clean. Use as low heat as possible. Heat the tube first till the Flux starts to bubble and then just a little bit more pointing the flame towards the fitting. Then start heating the fitting evenly around the base pointing the flame towards the tube. As soon as the solder starts flowing, use the heat from the torch to pull it to the base of the socket and move the torch around the base of the fitting in a half circle on each side starting from the point of solder entry.

If you overheat the brass, you have to pull it apart, clean it, and try again.

warno

The videos online are so confusing on the open vs closed topic. It would make sense to me to have them open to avoid pressure build up from heat expansion but then you go to another video it says close them.

Anyway I said hell with it and tried one of my own valves. I'll try to upload the pics to let you guys see how I did. But I'll write it as well. I'm using mapp gas for heat and had the valve open. I cleaned both pipe and valve and did my flux. I fit the pieces together and started heating. Now the pipe is about 2" from my wall so heating the back side was pretty awkward for me. I touched the solder to check heat input a few times before it finally went. I started to feather the heat around the joint while moving the solder. I put in alittle over 1" of solder maybe 2" or so. But it flowed in good. I let it sit for a bit then wiped with damp rag. And let it cool. The valve seat felt ok when I closed the valve. Now hopefully my pics work.

The second to last pic is best I could get off the seat.

The last pic is the back side of the joint. Should I be concerned about the faint line through the center of the solder?

ChrisJ

warno said:

The videos online are so confusing on the open vs closed topic. It would make sense to me to have them open to avoid pressure build up from heat expansion but then you go to another video it says close them.



Anyway I said hell with it and tried one of my own valves. I'll try to upload the pics to let you guys see how I did. But I'll write it as well. I'm using mapp gas for heat and had the valve open. I cleaned both pipe and valve and did my flux. I fit the pieces together and started heating. Now the pipe is about 2" from my wall so heating the back side was pretty awkward for me. I touched the solder to check heat input a few times before it finally went. I started to feather the heat around the joint while moving the solder. I put in alittle over 1" of solder maybe 2" or so. But it flowed in good. I let it sit for a bit then wiped with damp rag. And let it cool. The valve seat felt ok when I closed the valve. Now hopefully my pics work.



The second to last pic is best I could get off the seat.



The last pic is the back side of the joint. Should I be concerned about the faint line through the center of the solder?

Very hard to say.
It's one of those things that once you get used to it, you know what's going on while the solder is flowing. Kind of like when you're working on a pipe you drained, and are so sure it's dry but then you hear that crackling sound as you're soldering. Few things suck more than that.

I can almost always tell if a joint is good by how the solder flowed, not how it looks afterwards. If your pipe was clean and flux was applied evenly, but minimal on both the valve and the pipe chances are that's a very solid joint in my opinion.

Remember, with flux, less is more. All you want is a slight sheen on the metal surface, no globs.

warno

Ok. I'll wait until I test everything then find out. I only applied a thin layer of the flux since that's what I read up a few posts. I solder flowed nicely, hopefully it holds air.

Thanks for the compliment on my welds. Been doing that for awhile now. Lol

Pumpguy

I'm not an expert compared to those that have posted above, but when I solder copper tubing, I like to use a solder bearing flux.

As the flux heats, the solder that's in the flux melts and tins the joint, making the filler solder you add that much more likely to flow and completely fill the joint.

warno

I read about solder bearing flux, but until reading your post I didn't put it together that there's solder in the flux. I was thinking "why would anyone be soldering bearings?" Lol I tend to over think things sometimes.

rick in Alaska

That crack in the joint looks like a cold crack to me, such as if the joint was cooled too quickly. Solder job looks great though. My gut feeling would be to re-heat the joint and possibly add a bit of flux to the top to get it to flow out and then let it cool slow. If when you cool it you hear a small tick sound, then you need to re-do it.
Rick

warno

Ok. I did cool the valve body down I fear I had over heated it and had the seals baking. I'll dab alittle flux on it and heat it up. Thank you

Tinman

Clean the pipe and the fitting really well.

Use quality flux and solder. My preference is Staybrite #8 and Nokorode flux.

Wipe off the excess flux before heating.

This part is the key - you have to control your heat and you have to control your solder.

If you have too much heat or too little heat, you'll have leaks. Consider the size of the torch tip versus the size of the pipe you're soldering. Harris has some good charts on that subject.

If you don't control your solder, you'll be wasting a lot of it in places its not needed. And, it will look unprofessional.

Wear gloves and eye protection.

With your glove, wipe the joint if it doesn't look clean or you have drips while its still hot.

Beware of street 45's.

Harvey Ramer

Stephen.
What's your rub with street 45's? They are harder to clean because of the crease in the copper but if you get that crease clean... I haven't had a problem.

ChrisJ

Harvey Ramer said:

Stephen.

What's your rub with street 45's? They are harder to clean because of the crease in the copper but if you get that crease clean... I haven't had a problem.

Later on that evening.......................

I've had issues with street 90's as well. IMO it's not just the crease, they also fit odd and kind of loose.

Tinman

@Harvey - They are the bane of my existence. If I get a leak, bet the farm it'll be on the male end of a street 45. I think Chris is right. Poor fit? Or, the angle ever so slightly off - usually on 1 1/2" or larger.

Tinman

It was kinda tongue in cheek. That rare leak though is always those.

warno

Well that's not great news because I'm thinking I'm going to have a handful of each 90 and 45 street elbows. Ill be sure to double check the fit up before going to it.

ChrisJ

warno said:

Well that's not great news because I'm thinking I'm going to have a handful of each 90 and 45 street elbows. Ill be sure to double check the fit up before going to it.

warno

Are they really that bad? I can probably move some fittings around to avoid them, but they seem so handy to use in areas.

ChrisJ

warno said:

Are they really that bad? I can probably move some fittings around to avoid them, but they seem so handy to use in areas.

No, but they do cause problems in my opinion.
If you're testing with air, it's far easier to repair a leak than filling the system with water first.

Tinman

No. You'll be fine.

warno

I planned on testing with air. This being my first go round with sweating I don't want to have a bunch of bread floating around my system from pulling stuff apart and putting it back together after a water test.

Tinman

I'd like to be able to weld like you. I have to learn before I get to retirement because I want to repurpose things that will include both wood and metal.
Blacksmith too. We actually did some blacksmith metalworking in high school. That was awesome.

JUGHNE

For ball valves whenever possible I like to solder the pipes into the valve in the vertical position. I see for your application that is not feasible for these valves. I use a chain vise for the longer pipe, then the valve and the shorter stub of pipe.

If the valve is in a tight spot I have even "cheated" by doing this and then just use a coupling for the assembly. Or if a union is in the plan put 1/2 of the union on the short stub while in the vise and the other half on the fixed pipe.
If no vise then clamp long pipe with big "clothes pin" type clamps to parts cans or tool tray.

Before soldering I take the handle off after opening the valve and put that keeper nut back on those fragile threads. It keeps the plastic cover looking new. After valve is cool, I tighten up the packing nut on the stem that is under the handle. I might rotate the ball a couple times and snug the packing again. Put the handle back on. Often after soldering the stem packing will drip without tightening. (Learned this a long time ago after having to pay repairs on sheetrock ceiling, these things etch into your mind.)

Air test is good, you hear it before you would see water drip.
And your piping system is still dry for repairs.

For 1/2" copper if a lot of st 45/45 are needed I again "cheat" by using some 1/2" soft L copper. A spring bender will save a lot of extra fittings and can be made to look good. Also swage all soft copper for all sizes to avoid having to stock/locate couplings. (Usually not for 1/2 or 3/4 hard L)

warno

I have been a welder for 10 years now certified TIG and MIG for 9 of those. The welding part is easy for me. I half had the thought to abandon the 1" copper and go with our 7/8" stainless pipe from work then just weld the whole thing together. But then I bought a mess of copper fittings so I guess I'm going copper. Lol

Thank you to everyone helping me out. I'm going to be buying 2 sticks of 1" copper from work this week to get started on this project.

hot_rod

Here is a stainless sep that a welder built and shared a few years back.

Looks like a process piping welder.

warno

Funny you mention building parts like that. Before my wife's pregnancy complications took up alot of time with hospital visits I was going to build my own hydrolink.

I guess since it's my own thread I can take it off topic for a bit. Here's some pics of my recent welding on this project. At work we build industrial refrigeration units from either stainless, carbon, aluminum, and copper. On the very very rare case we get a copper-nickel unit.

The last pics are of the biggest unit we have built in our plant. It was an ASME U stamp unit. It was for a methane cooling unit. After the methane was pulled from a landfill it was compressed then ran through this to cool before running down the line. 10" sch 40 headers, 6" sch40 connections with flanges. There were over 1000 welds on this coil, me and the other guy working on it only had 5 leaks (4 returns, 1 header tube) in the first unit and 0 on the second unit. It was a good time.

hot_rod

Nice work, where is the shop?

There is a lot of stainless fab work done here in SW Missouri, plenty of food processing plants around.

You see a lot of pickup trucks sporting stainless steel racks, on the roads.

Paul Mueller is here and some of my friends have stainless fire pits built from "defective" tank heads. I have a 6' diameter stored here that a neighbor owns. Or use to own

warno

I work in Paxton IL.

We have defective parts too, hmmm funny how that works out.

warno

Well I did the air test tonight. Ran it up over twice what it would ever see. Checked it about 3 hours later the needle never moved. I'll check it again in the morning to see if it's still holding then bleed it down. I was most concerned about my valve sweat and it seems to be holding just fine.

warno

Yep, held air over night. All welds and sweats so far are good to go. I'll post some pics when I get going on the rest of the plumbing.

warno

Looking for any feedback good or bad here. Let me know what you guys think of my progress so far.

hot_rod

Nice pipe fitting.
Interesting transition at the air purger. What are the fittings on the plate HX?

warno

Thank you.

The fittings into the air scoop are stainless 1" sch40 bored out to except 1" copper then sweat together with 50% silver. The fittings at the HX are the same pipe setup with a 1" female NPT half coupler welded to one end then the pipe sweat on the other. There are 1" copper unions sweat on as well.

hot_rod

What, they don't sell copper to male and female adapters near you

Nice brazing work, I think you just enjoy melting and joining metals.

warno

They sure do sell those fittings but by putting the copper to stainless and so on I eliminate one or 2 thread fittings each time. Like I've mentioned before around here I hate thread fittings. The fewer I have to happier I am. I've had too many occasions where I thought "yep that's tight enough" and don't put a union or some other break point and I have a leak, resulting in me tearing half of everything back apart to reset.

I was told to go from copper to cast iron you need a brass nipple into the cast piece to avoid electrolysis and getting a leak at the thread. Don't know how true it was I didn't want to chance it.

And yeah, I like fire and burning stuff and melting things too. Lol