Best way to solder thin copper heat fins to soft copper pipe for radiator/heat exchanger with small butane blow torch?
Trying to attach 36cm (14") x 5cm(2") x 0.125mm(0.005") thick electrolytic copper heat-fins to 20 hollow soft copper tubes 6mm outer diameter, 0.4mm thick walled copper pipes.
Would ideally like to use silver based solder rather than tin-based. Is it realistic to use high-silver-content solder on such thin copper, and with a small butane blowtorch (has to be small as fins only 1cm apart)?
Can I use silver solder or do I need to use tin solder?
Any help/suggestions welcome!