Hi, thanks for the help.
Over here in France the majority of gutters on house roofs are made of zinc, the person who solders this all together in situ has a gas soldering iron with a large copper bit to conserve the heat, he rubs the iron on a white pad that is apparently a block of Sal Ammoniac acid which cleans the iron perfectly so that the solder will run easily and adhere to the iron. It seems that this could be the best flux for copper?
One thing that I have found in soldering copper (not tinning) is the heat, do not overheat it or it goes sort of oily and the solder will not adhere to it, even if fresh flux is applied to it, could this be the problem Pans perhaps also linked with a lack of abrasive cleaning beforehand?
Now that the method has been brought out into the open for us, now can someone shine a little light on where one can get pure tin?
As an aside I heard the other day that in Cornwall UK (the real home of tin-mining in England for centuries) someone is sinking a new shaft at one of the oldest and richest mines (Crofty I think) that has been closed for many years. The environmentalists are up in arms about it.
Thanks for your help
Pat