William Brown wrote:
I am going to replace the gate valves in my home the ball valves, so I
have been reading up on sweating joints. Briefly, the advice is to
heat the valve, then heat the line, then heat the valve while
applying the solder, then wipe the joint with a wet rag. My question
is, since there will be two joints at each valve, should I solder
both before wiping with the rag, or should I complete one, and then
do the other. I am a bit concerned that if I fully complete one, I
may undo it while doing the second, while if I wait to wipe until I
have done both, the first will have cooled to where the wiping will
be ineffective.

Others gave you good advice, but left out one step. Practice. Buy a length
of copper tubing and a few fittings. Solder a few joints.

Keep in mind, the solder is going to coat the tubing and the inside of the
fitting. It will be drawn into the fitting by the heat as the solder melts.
Once proper temperature has been reached, it only takes a couple of seconds.
For half inch tubing, it will take about 1/2" of the solder to make the
joint.

Try a vertical joint. You will be able to suck the solder up when you hit
the heated joint. If you want to be sure of what you are doing, make a
letter "P" with one fitting adapable to a hose so you can presurize it to
test for leaks. Put together the hose end, tubing, tee, tubing elbow,
tubing, elbow, tubing, elbow, finally one piece of tubing from the last
elbow into the tee.
--
Ed

http://pages.cthome.net/edhome