Plumbing 101 (Sweat Soldering)

[Mac McQuinn]

I need to replace a few plumbing components and have very little experience in sweat soldering. Is there a publication which gives a thorough explanation on doing this correctly? I'll be using lead free solder, ball valves, copper tubing and Hose Bibbs. My biggest concern is over heating the Ball Valves and Hose Bibbs. Any suggestions would be appreciated.
Thanks, Mac

[Jerome Stanek]

If you don't know how try shark bite fittings

[David G Baker]

I use ball valves for almost all of my plumbing needs but I do not sweat ball valves, I use threaded ball valves and do all of my sweating on copper fittings that screw into the threaded ball valves. I am always nervous about over heating the ball valve if I use the sweat type valves. The main thing you need to know is practice cleanliness. Clean all of your fittings with wire brush or sand paper until they shine. Use the correct soldering paste. Do not try to solder any fittings with any water in them because the water will create steam and the sweat joint will not seal. If you need to sweat near wood or other flammable items use a metal barrier or a product made to adsorb the heat of the flame. I keep a spray bottle filled with water with me all of the time to cool the fitting after soldering and to put out any accidentally started fires. I also keep a bucket of water with me and a grease rag to wipe off the soldered joint after the soldering in order to clean the acid from the solder paste and to cool the joint. Be careful with the wet rag because if you wipe the soldered joint while it is very hot the wet rag will create steam that may burn you. Practice, practice, practice. Be prepared for leaks. I have never done a large plumbing job with out at least one leak when the water is turned on. The more you do the easier it gets. Good luck. Time Life Books have very good information on plumbing. At one time Home Depot carried the books in the plumbing department and they may still. If not check the public library.

[Greg R Bradley]

Unless you have done lots of soldering and brazing on other things, I would suggest you do a house worth of pipe and fittings before trying hose bibs and a few houses worth before trying ball valves. Easy way around that is to solder threaded fittings and use threaded hose bibs and ball valves as David suggested. At least hose bibs are on the end and can be replaced later easily. Ball valves are in the middle of pipes.

[Mike Hollingsworth]

Quick tip:
When the flame turns green, that's copper oxide. Time to apply solder.

[Mac McQuinn]

Thanks for all the tips, the threaded Ball Valves and Hose Bibbs seem like a good idea to avoid heat build-up.
thanks,
Mac

[Ole Anderson]

I've done a fair amount of soldering, but today I needed to insert a shutoff so I could demo my kitchen sink and I used sharktooth ball valves. Pricy ($19 each) but saved a lot of time and hassle. And they work well when you can't get all the water out of the pipe. Although last time I added a soldered valve, I had to use the bread dough trick as I couldn't get the pipe to stop dripping.

[Mac McQuinn]

Ole,
Just wondering, does the Sharktooth system leave a rigid/stiff connection or is there a little lateral movement?
Mac



I've done a fair amount of soldering, but today I needed to insert a shutoff so I could demo my kitchen sink and I used sharktooth ball valves. Pricy ($19 each) but saved a lot of time and hassle. And they work well when you can't get all the water out of the pipe. Although last time I added a soldered valve, I had to use the bread dough trick as I couldn't get the pipe to stop dripping.

[Chris Rosenberger]

Mac,
Have you considered using PEX?
You can use a shark bite fitting to convert from copper to PEX. You can buy ball valves & frost proof hydrants that are made with male PEX fittings built in.

[Chris Rosenberger]

Ole,
Just wondering, does the Sharktooth system leave a rigid/stiff connection or is there a little lateral movement?
Mac

The shark Bite fittings have a small amount of movement.

[David G Baker]

Ole,
I have used the bread trick several times and it worked great except when it ended up in the valve mechanism of a very expensive bladder type toilet tank. There is a product that Menard's once carried that comes in several sizes that works like bread for stopping water from getting near the soldering. They look like a round capsule the size of the pipe. I went back several months later and couldn't find them. Wonder how well they work?

[Ole Anderson]

I am no expert in the area of plumbing, but over the years this is what works for me:


Make sure the pipe doesn't have any water in it, if it does, it will suck all the heat away from the joint and you won't get a successful solder joint
Clean the pipe and fitting with a stainless steel pipe cleaning brush
Apply a liberal amount of flux of the type compatible with your solder to both the pipe and fitting
Stay away from solder with a high melting point. Old lead/tin type works best but not for drinking water piping
Apply 80% of the heat to both sides of the fitting, the other 20% goes on the pipe
When the solder just starts to melt when touching the pipe (not the flame), heat it for another 10 seconds
Remove the flame and apply the solder to the top of the joint until it runs out the bottom, don't melt the solder with the flame
Let it cool without moving the joint
Wipe off the joint with a clean rag to remove any excess flux


It is a good feeling when you can solder up a pipe run of 10 joints, turn on the water and you don't get a leak.

My version of soldering 101.

But there is a reason so many are using Sharkbite fittings and/or Pex with a crimp fitting. Kind of like cutting dovetails by hand vs using a fancy router jig.

[Curt Harms]

A point I learned the hard way - make sure your torch produces enough heat. I soldered some 3/4" fitting with a pencil type tip and could never get a decent joint. Then I bought a self-igniting propane/MAPP torch with a bigger hotter head. MUCH better job and I wonder if a hotter torch might actually pose less risk to ball valves and such because a hotter torch will heat the connection part of the valve quicker so there's less time for heat to migrate to the heat sensitive part of the valve. I'm not a plumber so take that thinking for what it cost ya.

[David Helm]

One other point to add to what the others have said. If you heat the copper to the point of it changing color, you have over heated it. Go just past the point where the pipe melts the solder, and no further.

[Kent A Bathurst]

It's actually very simple to do. Clean the parts, apply the flux, heat the fitting, run the solder part way around the seam between fitting and the pipe, you're done.

FWIW - I also use ball valves, but for a different reason: SWMBO has a touch of arthritis, and the ball valve handles are very easy for her to operate. I also use threaded valves, and I put a union in-line 4- 6" away, to make the installation simple. But, the unions cost a few bucks. It's not like I do dozens of them, so the cost doesn't bother me.

One other tip - an 8" square of flexible thin sheet metal. When I'm up in the joists, I stuff this above the fitting, and hold it in place with some duct tape or a couple nails. Insulates the wood from the heat.

OH - one more: IF for some reason you have to remove a fitting - you heat it up and pull it off and throw it away. Never reuse a soldered fitting.

[Mac McQuinn]

Chris,
I'm not comfortable with PEX for potable water purposes and Sharkbites are too new for me to draw any conclusions.
Mac



Mac,
Have you considered using PEX?
You can use a shark bite fitting to convert from copper to PEX. You can buy ball valves & frost proof hydrants that are made with male PEX fittings built in.

[Jerome Stanek]

Shark bites have been around for a time now.

[John Lanciani]

Shark bites have been around for a time now.


As has pex. It just took a long time for it to be accepted here. Been in use in other parts of the world for quite some time.

[Mac McQuinn]

Jerome,
After they've been on the market for 25 years or so, I'll give them a closer look.;)
Mac



Shark bites have been around for a time now.

[Curt Harms]

As has pex. It just took a long time for it to be accepted here. Been in use in other parts of the world for quite some time.

I wouldn't be surprised if people remember an earlier experience with 'plastic' ( butyl? I don't recall the composition) pipe miles of which were installed in the '70s or '80s and had to be replaced because it failed prematurely. There is now skepticism about 'plastic pipe'.

[Myk Rian]

There is now skepticism about 'plastic pipe'.
It looks cheap, especially in a high end home.
My sister just had a home built, and it was all done with PEX.

When soldering, I take the valves apart first. That way I don't melt rubber parts.

[David G Baker]

Curt H.
You hit the nail on the head. No plastic for me especially inside of a wall. I have seen the thin wall copper pipe fail as well caused by acidic well water. I now live in Michigan so I do not put any plumbing in outside walls as well due to fear of freezing and rupture of the pipe from expansion.

[Bob Rufener]

Whichever method you use, you might check on you tube for instructional videos. I have used you tube for several projects and found the videos to be well done and informative.

[David C. Roseman]

[snip]
OH - one more: IF for some reason you have to remove a fitting - you heat it up and pull it off and throw it away. Never reuse a soldered fitting.
[snip]


I think this depends entirely on the fitting and the circumstances. :)

David

[Dan Hintz]

OH - one more: IF for some reason you have to remove a fitting - you heat it up and pull it off and throw it away. Never reuse a soldered fitting.

Yeah, I don't really agree with this one, either. I have pulled off plenty and reused, and I see no reason not to. Heat it up, wipe off the excess solder, reinstall. That has prevented a lot of second trips to the hardware store...

[David G Baker]

Dan H,
I agree. I have reused many used copper fittings. It may take a little more work to fit them but they are as good or better than new because they are already tinned on the inside.

[Ole Anderson]

Also there is a line of fittings that already have solder in them, all you have to do is wire brush the pipe and fitting, flux, assemble and heat. Limited to caps, bends and couplings, I believe.