John, My first company did silverplating and repairs to the public.
Things being what they were at the time we eventually decided to
outsource the plating. The tanks were as big as 8 feet long, huge EPA
considerations. I can give you specific info on jobbers if you email
Replating old pieces is problematic and therefor expensive. And
sometimes you just don't get the results you want. To get good
coverage in recessed areas higher voltage is needed which causes
frosting which requires more polishing which sometimes cuts thru the
plate requiring another replating process which you have to start
again from step one. Seams with tiny gaps can cause bleeding of the
cyanide solution up to months later. Base metal is another thorny
issue. Zinc die cast for example absorbs the electrocleaner solution
and leaches it out over time, blistering the silverplate. Sometimes
you will have applied pewter borders on copper sheet. You need an
intermediate plate to even things out.
I don't know the construction of your piece but a simpler way out
for you may be to just silver solder your joints(assuming its
suitable) then spot plate that area yourself and try to 'age' the
spotplate. Also if you are going to silver solder over previous soft
solder you MUST ENTIRELY eliminate the lead. At high temps the lead
will amalgamate with the base metal,creating a spongy new alloy that
is impossible to do anything with.
Given all those potential headaches sometimes a soft solder is the
pragmatic way to go. Polish and lacquer the repair.
If this is a customer's piece I suggest you discuss the situation.
If its genuine Sheffield and not just later silverplated copper any
repair, even if it comes out well, will adversely affect the value.
The line that worked well for me was. "as far as investment value
goes the piece is ruined already. but we can redo the piece for your
That's probably more than you wanted to know but hey, its 4AM and
and you brought back fond(?) memories.