I have found that when I solder kum-boo'd pieces I develop
problems with blistering and failure of adhesion. Is there a good
way to avoid these problems?
I’ve found 2 things to result in failure of adhesion: lack of
depleted silver surface and less than spotlessly clean metal.
For the first one, to save time, anymore I just use fine silver to
begin with. The advantage, besides time and being completely certain
I have a fine silver surface, is that I can still mark the piece as
sterling after adding the gold. The fine silver is generally stiff
enough for most applications. If you insist on using sterling to
begin with, deplete the surface at least 5 times, and 7 times is
The second is being scrupulous about the cleanliness of both metals.
I don’t use pumice, but instead use Ajax dishwashing liquid. This is
the plain stuff, not antibacterial or the stuff for automatic
dishwashers. It is extremely high in surfactants and strips off
residual oils, which is also important in etching. It does a job on
your hands too, and after you’ve washed both metals with it, you also
will not have any surface oil on your fingers or hands, so after your
session you’ll need some heavy duty lotion. Use a brass brush in
conjuction with the soap for highly textured silver, not necessary
for smooth metal, just be sure the water sheets off the metal. After
washing the metals and patting them dry, using really cheap paper
towels (nice paper towels have emollients in them which puts surface
oils back on the metal), wipe the metals down with alcohol swabs.
I don’t use the typical burnisher, but instead a dental wax modeling
tool that has a scooped spoon at one end and a rounded flat spatula
at the other, both ends highly polished. Polishing keeps them from
dragging. My two other tools are a basket weaving awl needle and a
darning needle, inserted into wooden dowel handles. These ones get
down into the bumpy surfaces of reticulated silver.
I think if you pay attention to these two things, you’ll find you
have much better success. The adhesion will be almost instantaneous
(I stick my metal on the plate, turn the fire on high and go do
something else for 20 min.), and you will not have problems with