Possibly I can help shed a little light on standard polishing practices.
The routine I generally follow on rough castings is this:
(1) Finish the inside. If very rough I might use a half-round file.
Usually I’m able to use a cratex wheel followed by grey star (or tripoli
etc) on a felt finger. I might rouge the inside with a small buff on a
flex shaft for a superior finish.
(2) Use a sanding disk to remove sprue and generally straighten up the
casting, remove parting lines, etc
(3) Use a knife edge pumice wheel (Gesswein GK-90 is the best) on the
flex shaft to clean up some of the sanding marks where inaccessible to
buffs or laps.
(4) Use a small brush on the flex shaft to get around prongs, down
grooves and hard to reach places, polish inside the heads with end brush
(5) Use a highly polished tool steel round tapered-to-point burnisher to
clean up areas of the ring no brush or wheel can reach. A highly
polished miniature three cornered file (scraper) also works wonders.
(6) Use a 4", 5", or 6" properly dressed hard (usually flint or diamond
hard, and usually 1/2’ thick or so) felt lap (with tripoli etc) to
prepolish all the flat areas (sides mostly). Lapping is a dearly held
secret of most professional polishers, it can make or break a piece. One
of the tips for good lapping is to continually dress your lap with a
stone, keep it FLAT as possible, flat and smooth and true running. Cut
the backside at a 45 degree angle to an edge with the cutting side.
Lapping is a skill that develops over time and you’ll want to use a
light touch until you’ve got it down. Really good polishers sometimes
use a hard-rock maple lap to put a mirror finish on flats, especially on
platinum. Those guys are really good. I know polishers that use laps
made from all kinds of different materials, anything that works… You
can always cut a lap to whatever angle or curve you want too.
(7) Use a tripoli buff (I prefer treated muslin) to generally prepolish
without losing the edges created by the lap. Always polish parallel to
edges, never across edges. I try to pre-polish as dry as possible.
(8) Use a rouge buff with standard red rouge, Fabuluster, zam, etc, to
finish polish. I try to rouge as dry as possible.
(9) Clean in ultrasonic cleaner (I use the old standard, Mr. Clean and
ammonia, however many new and powerful cleaners are available)
(10) Clean and dry with a steamer if you have one, blast with air, or
dip in denatured alcohol etc.
tip: don’t over polish, don’t load up your buffs with compound unless
it works for you (doesn’t work for me)
tip: don’t polish away the edges, they give a crisp clean feel to the
Keep flats flat, rounds round, curves even, straight, clean, no waves…
These steps are very basic, there are very many variations according to
the ring design and material. A professional polisher’s workstation will
frequently have a board onto which are hung up to 10 variations of laps,
many different felt bobs, many different hardnesses and sizes of
brushes, several different buffs of each tripoli and rouge, finger
buffs, and who know what else…
I’ve really only touched on finishing here, it’s a vast subject, easily
worthy of its own book. hmmmmmm gives me an idea…
Handmade 18K, 22K, and platinum gemstone fine jewelry.
Diamond setting, rubber/metal molds, casting, lapidary
Die and mold engraving, plastic patterns for casting.
Cad jewelry design, cad/cam milling scroll filigree…
P O Box 2057 Fairfield IA 52556 515-469-6250