ok.. so here is my 2 cents worth... I finally got the hang of this the other day..... you MUST clean both pieces with sandpaper.... then apply flux inside and out of the two joints.... then you must heat the pipe with the TIP of the blue flame... you will hear the flux sizzle... (if you are using a benzomatic... it says 7-10 seconds for heat then touch solder, this isnt long enough)... once the pipe is hot enough.. and it will change color to a somewhat darker worn looking cooper you can then touch the solder to the pipe... if it doesnt immediately spread around it.... the pipe isnt hot enough... you will know that it has completely sealed when you either see or hear a drop of solder fall from the bottom of the joint you are soldering ( I put a little bowl of water under where I was ..... for two reason... in case of a small fire... and so that the extra solder had somewhere to go besides my brand new vinyl I just laid)..... It takes practice... just be patient... my first joint was slow... second a little faster and third was instant!!!!!!!! Also... I would wait a few minutes to let the copper cool before I tried to twist anything attatched to it.
Hooray... I finally get to help with something...... (ps... there are pics of my joint on my 'what happened to my kitchen' thread)