Pieces made of different metals

I am interested in starting to make pieces of different metal (ie.
White and yellow gold together, etc.) and would like to know if
anybody can refer me to a good book that would explain the process.
I know pieces have to be cast separately to then fit together, but I
look at some pieces made of different metals and cannot figure how
they are soldered together. There must be ways that are better than
others to carve the wax patterns so that once fitted together they
can be easily soldered which will offer the best look. Any help would
be helpful. Thank you. Roland Gagnon Saint John, NB, Canada

Here is one tip…

One thing to be wary of when casting pieces which will fit together
is the shrinkage factor. A piece that is much thicker than another
will shrink more, and perhaps unevenly, so compensation may be
required. As an example, back in about 1975 a jeweler approached me
to mold several pieces to be cast into gold and fit together. They
had different thickness, and as a result, were not a close enough fit
to be used. In that case, there were 3 shrinkage factors, the mold,
the wax, and the cast metal. As a general rule, pieces of the same
wall thickness will shrink similarly.

Personally, since I do cad/cam work now, I usually mill wax patterns
which must fit each other, or use Rapid Prototyping. I am usually
able to achieve a close fit.

Jeffrey Everett