I’m new to fabrication and can’t get the bottom soldered to the wall
of a round copper box. I have successfully soldered in the past, but
not something this large or that is of 20-gauge material. Here are
some other details:
-Box diameter is 3"; the sides are 1"-1/2" deep
-20 gauge for the sides and 22 for the bottom
-Air/acetylene w/#1 tip
-Medium wire solder chips approx. 1/32" long and spaced about 3/8
apart on the outside of the box
-The soldering is done on a charcoal block and I’ve put firebricks
around three sides of the box to hold in the heat.
-The copper is clean and the fit is tight.
-The solder chips don’t melt at all before the rest of the box is
solid black. In fact, they don’t melt at all.
All help will be much appreciated.