Any tips on polishing platinum?
Sure, after your rough, then fine filing, do your sanding (I use
a sanding stick), then go to a finer grit, then go to a finer
grit... until you get to 600 grit. The 600 grit leaves a pretty
good finish. I use a variety of laps, both soft and hard to get
all the different curved surfaces. The old time polishers used
wood laps for the truly flat surfaces, they take a bit to get
used to, but oh what a finish! You can get polishes specially
formulated for platinum from Gesswein or others, and you'll find
they help significantly. Certain areas of your casting may
require the use of a polished burnisher, I have found that either
highly polished agate or carbide works well, the agate is an old
favorite. Many jewelers like to burnish the entire surface before
polishing, and I frequently do this as well, you seem to get a
higher polish when you do. Consider getting your casting in 95
cobalt platinum, it's a better metal than 90 iridium platinum
(personal opinion). By the way, the best lubricant I've ever run
across for drilling platinum is lanolin.
Jeffrey Everett, jewelry craftsman
Handmade 18K, 22K, and platinum gemstone jewelry.
Diamond setting, rubber/metal molds, casting, lapidary
Die and mold engraving, plastic patterns for casting.
Jewelry design, cad/cam, milling, scroll, filigree, & more.
P O Box 2057 Fairfield IA 52556 515-469-6250