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[Lu47Dan]

Silver soldering or silver brazing is not hard to learn and in the following pictures and text I will try to show three things , how to anneal copper pipe , what you need to do to make a home made "pulled" tee in the side of a piece of copper tubing , and what a silver soldered joint looks like .
Silver soldering and annealing requires much more heat to do the soft soldering does , annealing can be accomplished at lower temperatures then silver soldering but in the case of manually forming a tee the copper must be very soft or it will crack . The first step in this process is locating where the tee needs to be . I used a Uni-bit to drill the hole out to 5/16" , you do not need to clean the tube unless it is real dirty . The next step is to heat the tube until it is red hot this will anneal it to dead soft and make it easy to from the socket for the 1/2 pipe that I will solder in later on in these pictures . If you need hard ends of the pipe wrap wet rags around the ends before annealing the tube . You can vary the heat to vary the softness of the copper but it is a learned skill . Let the tube cool until you can safely handle it , while you are waiting round up a small tapered pin punch , not a center punch , and a small light ball peen hammer . Insert punch into drilled hole at a angle and tap the side of the punch to start lifting the lip that will form the socket , progress around the hole until you have a uniform lip about an 1/8" high , stop here and get a larger tapered pin punch and repeat the process , checking hole size with tubing you intend to use , until you have a snug to tight fit . You should not have to hammer it into the socket , it should slide in with some resistance or when you heat it to silver solder , it will fall in . After inserting the tubing into the socket you can mark it for depth , use a magic marker don't use a pencil . remove the tubing from the socket and use a file to fish mouth the end of the tubing the same as the radius of the tube you are soldering it into . Insert the tube back into the socket make sure to line up the radius with the tube and apply heat to the joint until it starts to show a red glow touch a stick of silver solder to the rim of the socket while still heating it , solder will began to melt , heat until solder flows and is drawn into the joint , work the solder completely around the joint and you can see that the joint is sealed , remove heat and let the joint cool . Once cooled you can put the joint into service The 5/16" hole works for 1/2" Copper tubing I have not tried it for 3/8" yet but I think it would be too big , Drill the hole 1/4" for 3/8" tubing .