My experience (long ago) with plating is that it is, in any
situation, a somewhat unpredictable beast. While there is the
standard list of do’s and don’ts (most of which your post indicates
you’re aware of), the mix of equipment, solutions, current levels,
and workpieces often requires “adjustments” to rules and techniques.
Given that you are talking about small pieces, and silver at that, I
would recommend a series of controlled test runs, some with nickle
pre-plate, some not; some high current, some low; etc. Keep notes,
look at the results, and let us know how it all turns out.
L.F.Brown Goldwork, Inc.
17 Second St. East, #101
Kalispell, MT 59901