2) The ladder rung is placed and a bit of flux is added around the ladder rung - around = between
3) Heat and done. I wonder, heat locally? Or won't the other parts loosen and fall off? - not terribly, only did not fall!
If this is the process, do you need special tin? - no, usual for soldering the electronic details.
I've tried brazing, but that doesn't work at all for small parts. Also, the torch keeps blowing most parts away or evaporates the metal - try begin from afar, trays neatly, briliance of tin will show the result.















