solder

Anyone know if there is a way to save a kettle with a joint that has burnt flux residue embedded in it? I tried a neat little coil of solder around my triclamp fitting, and evenly brought the surface of the kettle up, and then applied heat to the fitting itself, but the solder took a long time...

We need to upgrade the transfer lines from the sparge water to the Mash tun. I'd like to solder some copper joints. If these joints heat, as the will when heating, I’m thinking there might be concern about the tin and antimony leaching out, or the joint softening. There will not be water in...