Q: What steps should I take in order to get a good polish on sterling silver
A: For rough cutting, (assuming you've already emeried or otherwise cleaned
up the casting) you can use bobbing compound (real fast), brown Tripoli
(almost as fast), which leaves a slightly higher prepolish surface, or white
diamond Tripoli. The latter allows greater precision. I prefer it for
custom work, but for production work it is a bit slower.
Use any of these on whatever buff you prefer. I like the treated stitched
yellow ones. Soft to medium felt wheels will cut very fast, if your surfaces
can be reached with such a buff. Obviously, for fine, sharp lapping, the
harder grades of felt lap -or better yet- a split-lap wheel on an appropriate
machine, is the choice. Some people like bristle brushes (which are usually
charged with bobbing compound or brown Tripoli) for coarse cut-down.
For final finishing, the usual choice is red rouge on a soft muslin wheel,
either stitched or not, as is your preference. I like the lead centered
unstitched ones. Red rouge with silver gives the very highest polish.
However, it is very important with red rouge to take pains to keep the wheels
from becoming contaminated with coarser compounds, or you'll get faint scratches
instead of your dead-sharp polish. The rouge just doesn't actually cut
to eliminate such scratches well, as the wheel puts them in, if you've gotten
grit or coarser compound traces on it. That means you need to clean the
coarse compounds off the piece before final buffing, and storing the rouge
wheels in a plastic bag between uses.
If all that seems too much of a pain, you can use some of the slightly faster-cutting
types of rouge. Yellow rouge is very good on silver, and gives almost as
high a polish as the red. "Zam" (green rouge) is another good
performer. Both of these are a little better at dealing with slight contamination
on the wheel or carry-over of coarser compounds.
There is an expensive orange platinum rouge, (basically an alumina polish)
made in Germany and sold by Gesswein, which is also good at giving a very
high shine while not allowing a slightly contaminated buff to scratch the
piece. But this stuff is costly, so I don't suggest you go buy some just
for silver. If you've already got some around, and find your red rouge
wheel is leaving a haze of fine scratches, a little of this may help to
improve matters. A better plan, though, is to avoid such contamination in
the first place by thoroughly cleaning the work between polishing steps.
Silver, in general, is a little difficult to polish really well. You must
be careful to keep the piece moving, in the sense that the direction of
the polishing action must be sweeping across the piece and changing constantly,
in order to avoid "drag lines". Much more than gold, it can tend
to show these drag marks if you're not careful, or if the metal isn't perfect,
which is the case with many castings. And then, when you've got the thing
finally perfect, if you leave it in an ultrasonic cleaner for too long,
cast metal will often give you frosted "etch marks" or streaks,
as the powerful ultrasonic waves seek out imperfections in the surface,
and attack them preferentially.
Barring that, even once you've got it all perfect and cleaned, you have
created a surface that cannot be touched by human hands without destroying
the polish instantly. It looks great for show, but is not very useful,
due to silver's softness. For this reason, much commercial silver isn't
actually polished out to its maximum, but is only well tumbled in steel
shot, with perhaps a quick "fluff" buffing, or is left with a
white diamond Tripoli finish, which is still a pretty attractive shine,
without the real high "color". That sort of surface will show
fingerprints and faint scratches less.
Larger items like hollowware are often not actually polished, but are instead
"scratch brushed" with a wet, lubricated, nickel- silver wire
brush. This leaves the so-called "butler's" finish, which is durable
and attractive. It's a burnished and bright look, with faint but bright
scratch marks showing uniformly all over. That same wet brass or nickel-silver
scratch brush is also a great way to finish out the black antiquing you
achieve with liver of sulfur, if you're doing that. This converts the dead
dull black to a shiny metallic gunmetal blue/black color that lasts much