Copper Pipe soldering technique

[glenn kangiser]

Since this has come up recently I thought I'd put a little blurb in here.

Info on soldering copper pipe.

1.  Measure and cut pipe to length.

2. With emery cloth or  sandpaper or  wire brush clean both areas to be joined to bright metal.

3. Apply flux to the just cleaned surface on both pieces.  There are many types.  Pink fluid, paste, tinning paste.  It should be for copper water lines.

4. Apply heat to the joint - not the solder- neutral flame- no excess carbon especially if using oxy/acetylene (not used by most)  - fairly evenly - all around - this means you may have to heat from two sides as the heat will flow around the joint a bit.  Watch out that you don't set the wood on fire. A hardware store type turbo torch using propane cylinders will work as will others.

Using water pipe safe solder - usually tin/antimony but there are others - apply the solder to the heated joint.  If cleaned and fluxed properly and hot enough, capillary action should draw the melted solder right into the joint.  It will flow most of the way around by itself but for good measure, wipe the outside line of the joint with the end of the solder.  I like to use about 1/8 inch diameter solid wire solder.

If the solder isn't drawn into the joint you may not have cleaned to copper enough to get all of the oxidation off.  You may not have fluxed well enough to keep the copper from oxidizing when the torch heat is applied.  Oxidation will stop the solder from adhering to the metal.  It can happen in a couple of seconds of torch heat on unfluxed copper.

If the solder isn't drawn into the joint, heat a little longer.  

Total time to solder a cleaned and fluxed joint should be around 10 to 20 seconds depending on the torch, your skill and position.  Note that this type of soldering can be done in all positions - even upside down if joints are properly prepared.

Allow  it to cool.  You should be done.  Check once more for fires.

So there you have it.  Happy fluxing.

[desdawg]

My PVC keeps shriveling up when I touch the torch with it. Oh, this is for copper. Never mind.  [smiley=evil.gif]

[glenn kangiser]

Darn it, desdawg -- I guess I thought if I put it in the title that would be enough.  I guess I better go back and put it in the text so you don't kill yourself with dioxin. :-/

[glenn kangiser]

Now that you mentioned it, desdawg, there are materials for welding plastic.  They use a heat gun with a special nozzle to direct the heat for welding, and plastic filler rod.  Maybe I'll have to give it a try sometime just so I will know how well - or unwell it works. :-/

[Doug Martin]

Total time to solder a cleaned and fluxed joint should be around 10 to 20 seconds depending on the torch, your skill and position.

You must be using MAPP gas -- it always seems to take me 60-90 seconds to get the fitting warmed up using normal propane.  I wonder how long a plasma torch would take...  

Oh, one helpful hint that I'm sure you have used Glenn but maybe others haven't -- if you are soldering an enclosed 1/2" pipe that has a bit of water in it and you don't have a way to let the steam escape a bit of bread bunched up and shoved into the pipe 3 or 4 inches past the solder point will keep the steam away from the fitting and will let you get a good solder.  If you don't keep the steam away then you'll get a cold solder.  The water pressure will blow out the bread in a few minutes after you run it full blast once the solder is in place.

[glenn kangiser]

I usually use oxy/acetylene cranked a bit low.  

I always have a few bottles around.  Possibly I forget how long it actually takes with some of the other torches.  I forgot about the bread - I think you may have mentioned it in another thread - good idea.  Thanks for bringing it up again.  (Now I sound like a baby bird). :-?

I just though we may want to collect all of this together in one easy to find place.

[Ernest T. Bass]

I would say 10-20 sec. for the solder flow is an accurate guesstimate for me, using a propane torch.. I've learned to really crank the flame on th 3/4'' joints, or it takes FOREVER.

[glenn kangiser]

Sounds about right to me.

[desdawg]

I have a Harbor Freight plastic welder. It connects to 110v AC and about 10psi of air. The problem is all plastic is not created equal so finding the correct "rod" of filler material is difficult. I have repaired PE water tanks with this tool but I had to remove some plastic from another part of the tank to have material that would fuse. Yellow PE gasline and white PE water tanks are not compatable materials. The little plastic welding rods that came with the welder haven't been of any use to me to date.

[tc-vt]

You can protect flammable surfaces from the torch flame with a fire retardant insulating material designed for this purpose.  It can be purchased at any hardware store.  Keep a wet towel and fire extinguisher nearby.  

The MAPP gas is much better than propane, especially if you are working with
3/4 inch or larger pipe and fittings.  Get the automatic igntion torch head which lights when you push the button and extinguishes when you release it.  With this torch you don't have to wonder where to lay down a lit torch.  

Reaming the inside of the pipes after cutting is a good idea too.  This smooth surface inside the pipes is supposed to be better for water flow and reduce the chance of noise at high flow rates.  You can ream with the reamer attached to most pipe cutters, but better than that is a blade reamer which has a short hook shaped blade which you run in circles inside the pipe.  The tool probably has a name but I'm not coming up with it.  It does a better job than the reamer on the pipe cutter with less wrist fatigue.  It's also a good way to slice your finger badly if not careful since it is very sharp and it is easy to slip when using it.  (fortunately I don't know this from experience but it is the warning given to me by the guy who sold it to me).  Here's a picture.



Tom

[glenn kangiser]

Good points, Tom.  I like to  use a sawzall with a pretty fine tooth metal blade also to cut sometimes.

[glenn kangiser]

I have a Harbor Freight plastic welder. It connects to 110v AC and about 10psi of air. The problem is all plastic is not created equal so finding the correct "rod" of filler material is difficult. I have repaired PE water tanks with this tool but I had to remove some plastic from another part of the tank to have material that would fuse. Yellow PE gasline and white PE water tanks are not compatable materials. The little plastic welding rods that came with the welder haven't been of any use to me to date.

Thanks for your experience on this desdawg.  I wondered how well it actually worked.  I was going to reply the other day, but somehow got distracted -- wardrobe malfunction or something. :-/

[firefox]

I wonder if they make an electric heater that clamps around the joint and heats by induction
similar to the electric soldering guns that weigh a ton.
Bruce

[glenn kangiser]

I haven't seen that one.   I prefer the oxy/acetelyene as it really gets with it but you have to be careful -it can do damage.  I run it low.

[desdawg]

I have done both socket and butt fusion on PE gaslines. There are special tools and the welding temperature is 500 degrees. A socket fusion iron has special socket faces that attach to the iron, one for the exterior of the pipe an one for the interior of the fitting. For butt fusion there is a special machine that aligns the pipe. Once the two pieces of pipe are aligned you back the machine off, insert your 500 degree iron and heat the pipe ends for the appropriate length of time, remove the iron and bring the pipe together. The fusion joints are stronger than the pipe itself. Glue and primer on PVC are considerably easier to use.  8-)

[glenn kangiser]

Interesting, desdawg.  I've seen it from a distance and seen the result but didn't know how it was done. Thanks