Hi again Andrew:
I re-read what I sent before, and realized a couple of things.
(A) I’m not sure where I got the idea your ingot was discolored.
Late night reading of ‘decoration’ I guess. So, no, you can’t buff
off the decoration, you’ll have to face it off. I still recommend a
fly- cutter large enough to do the whole thing in one go.
(B) You’ll want to get the surface up to whatever polish level you
want before you do the detail milling. Buffing rounds the edges of
details, especially in the hands of beginners. I imagine you don’t
want your letters to have radically rounded edges and oddball
erosion lines all over them.
Thus: fly cut both faces, then get a couple of sheets of emory
paper, in 220, 230, 400, and 600 grit. Put the paper flat down on a
sheet of glass, and proceed to sand the faces of the ingot. The
important part is that you go back-and-forth in a single axis per
grit. (eg. sand back-and-forth in the long axis of the ingot for the
220 grit, and then back-and-forth in the short axis of the ingot in
the 320 grit, then at 45 degrees for the 400, and so on.) The idea
being to sand with the 220 until the milling marks are gone, then
switch up through the succeeding grits. The reason for changing the
axes is so that you can see when the marks from the coarser grit are
gone. It’s hard to describe, but you’ll be able to see it once you do
it. Keep going with whatever grit you’re using until all the marks
from the preceding grit are gone. A little water on the emory paper
will help keep it from loading up with silver particles.
After that comes buffing, which you really want to be doing with a
larger (4-6" dia) buff on a real buffing machine. Starting with
tripoli. However: buffing can be dangerous for beginners, both to you
and the piece. I strongly recommend you pick up a couple of intro
metals books and review their sections on buffing before moving into
this phase. (Tim McCreight’s The Complete Metalsmith is the
standard basic text. I’m not sure where you are, but it’s common
enough that local bookstores might just have it. Failing that,
Amazon certainly does. Get the Pro or the Pro+ edition. ) I’m
reasonably sure there must be buffing tutorials out on the web
With that thought in mind, 20 seconds of googling provides this:
It’s aimed at either auto-body or motorcycle folks, so not
everything translates to jewelry, but it’s not a bad overview of ‘how
to buff big things.’ (Ignore their compounds, those are for
auto-body work, not jewelry.)
Once you have a nice flat mirror, then you can start milling on