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WMorg555
Jun 21, 2009, 03:37 PM
I'm replacing old piping with new 1/2 inch copper and I'm trying to solder the joints together and add new ball valves. I followed the direction exactly as I read in a plumbing manual-I cleaned the joints and used abrasive paper to get them shiny, I put flux on both parts going together and I heat the connector until it smokes a little-but when I put the solder on the crease it just sits there even when I am still holding the torch. The manual says that when you heat the joint and just touch the solder it should melt and the flux draws it into the joint. My solder just sits there until I put the torch right on the solder and then I have blobs of solder around the joint. Is it okay to leave it like this or is it a problem when the solder looks like an uneven blob? Thanks for any advice.

massplumber2008
Jun 21, 2009, 03:54 PM
Hi wmorg...

You need to shut the water main, drain all pipes in the house... open all faucets (including outside faucets)... leave them open and then do all that you said.

What kind of heat are you using.. If propane then no surprise here as this is slow to heat. I recommend MAPP gas... see image.

You do want the solder to flow when you touch to the pipe. Direct the flame at the fitting so it SUCKS the solder into the joint. DO not leave any BLOBS hanging on as they will most likely leak. You want to heat the bottom of the fitting first, apply solder, wipe excess solder off and then heat the top joint. The top joint will not take as long to heat as the bottom joint.

If still unsure then practice on a few fittings before starting to work with the old pipes/fittings, etc.

Let me know if you have more questions...

MARK

hkstroud
Jun 21, 2009, 03:59 PM
Apply the flame to the fitting. Heat until you see the flux begin to run. Touch the solder to the joint. The solder should begin to melt shortly thereafter. Heat one side of the pipe or fitting and appy solder to the other side. That way you will know that the pipe and fitting are hot enough all the way around. The heat of the pipe or fitting is used to melt the solder, not the flame of the torch. Wipe of excess solder with wet cloth. The size and length of the pipe will have an effect on how long it takes to get it up to temperature.

creahands
Jun 21, 2009, 08:41 PM
Mark is right. Make sure no water in line.

Chuck

dmrlook
Jun 21, 2009, 09:34 PM
Sometimes it is very difficult to get all the water out of the line no matter ow long you wait (unless you can wait overnight for it to fully dry out which is usually hard when you need water). A neat trick is to take some bread and stuff it in the pipe that is still wet. Push it in there with a screwdriver. It will help hold back the moisture long enough to get a good joint. Then, when you turn he water back on, it will fall apart and come out the faucets. Just be warned that some of your aerators will get clogged and need to be removed and flushed of bread particles. Not sure if the experts would recommend this, but it worked for me like a charm.

Good luck,
Rob

massplumber2008
Jun 22, 2009, 03:53 AM
Hi Rob:

Here's what I tell most people...

If all pipes are opened and drained there should be no need for any "tricks"... ;)

If after opening all faucets (including the outside faucets) there is still water issues then the connection at the water meter outlet needs to be cracked to allow water to drip at that fitting as it is likely that the main water shutoff is malfunctioning.

There can also occasionally be a siphoning effect at times where water gets pulled from a water heater, for example, when draining systems down and that causes difficulties with soldering. In this case, draining water from the heater seems to fix this issue.

Finally, if pipes are below a level that they cannot be drained properly you can use a wet vacuum to pull water out of pipes and/or you can BOIL the water out of the pipe using a torch to a point that you can solder.

In all my years, if I followed this advice then I never had issues soldering.

Just FYI... :)

MARK

iamgrowler
Jun 22, 2009, 07:11 AM
Hi Rob:

Here's what I tell most people...

If all pipes are opened and drained there should be no need for any "tricks"...;)

If after opening all faucets (including the outside faucets) there is still water issues then the connection at the water meter outlet needs to be cracked to allow water to drip at that fitting as it is likely that the main water shutoff is malfunctioning.

There can also occasionally be a siphoning effect at times where water gets pulled from a water heater, for example, when draining systems down and that causes difficulties with soldering. In this case, draining water from the heater seems to fix this issue.

Finally, if pipes are below a level that they cannot be drained properly you can use a wet vacuum to pull water out of pipes and/or you can BOIL the water out of the pipe using a torch to a point that you can solder.

In all my years, if I followed this advice then I never had issues soldering.

Just FYI...:)

MARK

I usually turn off the H/W tank to prevent siphoning it, open the highest hot/cold tap in the house to break the suction and then use a Wet/Dry shop vac to suck any remaining water out of the piping system.

Works like a charm.

KISS
Jun 22, 2009, 07:25 AM
Valve open? Correct solder? Practice with a tube and fitting on top and vertical before graduating to valves.

KISS
Jun 22, 2009, 09:01 AM
Now that I can type a longer response, valves are particularly hard to solder because of their large thermal mass and the possibility of damaging the seals or seats. To avoid damage the valves should be open ans so should some of the taps connected to the valve.

Poorly soldered joints and/or cold soldered joints will bust, so you need to get it right.

Taking a coupling and placing it on top of a piece of copper held in a vise is a gooood way to practice.

Prepare the pipe and fitting. The specific tool saves lots of time. Put the pipe vertical and the fitting on top. Heat the fitting and not the pipe uniformly. Apply solder to the OPPOSITE side. This will assure that the pipe is melting the solder and not the torch.

If you want a nice looking joint, you can wipe the joint after it cools slightly with a damp rag.

Make sure you are using a plumbing solder which is tin/Antimony based and not a silver solder which has a very high melting point.

KISS
Jun 22, 2009, 09:22 AM
I also need to pint out that there are couplings and repair couplings because of the nature of the work you are doing.

Couplings prevent a tube from sliding through and are used to extend newly placed tube.

Repair couplings don't have that depression or groove that prevents a tube from sliding through, thus tubes can be soldered when they are fitted nearly together.