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How to use aluminum oxide powder for polishing

Dear Friends,

I’m starting to learn Faceting, and for polishing I have copper lap

For first step I’m working on glass and for polishing I have bought aluminum Oxide powder.

My question is that with aluminium oxide powder ( 1 micron , 22000 grit) and a copper lap how I can polish? How can i make paste?


Mix oxide with water and Apply with a brush. I personally never used a copper lap but if you get scratched you need to dress the lap. There is instructions on YouTube. If the copper lap been used with something else you might have to resurface the lap.

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First a simple but important principal: One lap - one grit. NEVER use a lap for different grits as the grit embeds into the surface of the lap.

Copper laps are used for pre-polishiing, 3000 or 8000 normally, then you move to the polishing lap of which there is a plethora, covering both synthetics and metal alloys.

I have one synthetic, a Lightning Lap precoated with Cerium, all other polishing laps are either Tin, Zinc or cast iron depending on the stone and I use 50k DeBeers diamond in the most minimal amount, ie, a little bit of baby oil on the lap, smear with diamond then wipe off, the fractional amount that remains embeds into the surface and polishes fast provided the pre-polish and polish laps are flat and true.

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Treat it as though it were cerium oxide. Put 3 small spatula scoops into a small vesicle and enough water ( teaspoon full, 5 to 10 ml) to make a thin suspension and use as such. Nothing complicated. When your disk gets too white, dip your brush into plain distilled water, for a few cycles. Generally Alumina A is used on a tin lap such as a Batt lap. Works very well. I have just finished a lovely garnet with it, without any problems. Be careful with glass, it can be touchy at times. Why glass when quartz is inexpensive and readily available.

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