For those home owners who insist on doing there own plumbing projects here is a little guide to assist you with the soldering of the copper piping used in home plumbing systems. First I should point out that if you do your own pluming installations you should have a general idea of the codes governing such installations. You can find the codes for your state at the link below.
Soldering copper pipe is not as difficult as a lot of people think it is. The number one requirement to a successful soldering experience is cleanliness. Thoroughly clean the inside of your connections with a wire reamer brush that you can buy at any hardware or plumbing supply store. Now thoroughly clean the out side of your pipe at least 1 inch beyond the end of the fitting with emery cloth or steel wool. It's also not a bad idea to de bur the inside of the pipe with your pliers. Some pipe cutters come with a triangular blade sticking out of its back, this is a de burring tool. Use it to remove any debris left from cutting the pipe that may hinder the soldering and cause a leak.
The next step is to apply the flux. The flux acts as a cleaning and bonding agent so that the solder will adhere to the copper and form a good tight and strong joint. Be sure to apply the flux liberally and beyond the fitting to be sure no dirt or dry spots cause the solder to not stick properly.
After assembling your joint take your torch and with the tip of your flame heat the middle section of the fitting alternating sides for evenness. With your solder extended touch the joint. Keep heating until the solder melts. Now remove the heat and melt about 3/4 of an inch of solder into the joint. The heat will draw the solder into the fitting all around. You should see the solder as a ring around the entire joint. Now wipe off the excess with a rag and your done. Move on to the next joint simply repeating the same procedure.