If that Oxy/Mapp kit uses those small 14 oz. gas cylinders, you'll probably find you just about get the metal hot enough to start welding by the time the oxygen bottle runs out, BTDT. For gas welding, you really need acetylene for the right heat. The is probably why they give you brazing rods with those Mapp "welding" kits <img src="/forums/images/graemlins/smile.gif" alt="" />

You might see if your local community college offers a night welding class. Will be money well spent to try the various welding systems and get some hands-on time with them.