We are looking for a vendor capable of Optical Polishing. Very interested in the level that can be achieved and proven. Also interested in learning more about steel selection to hold a good polish. Our current steels are 420SS and H13. We are leaning towards H13 because it seems to be easier to polish and holds a polish longer. Any advice would be great.

Have you considered nickel or nickel-cobalt alloy rather than tool steel? The mirror finish as you require can be obtained on nickel and nickel alloy molds by electroforming them directly onto a mirror smooth surface. To obtain the mirror smooth mold surface, the electroforming mandrel (or original) is prepared using fluidized coating materials such as lacquers, waxes or photo resists. The mandrel surface is metalized and the nickel or nickel alloy deposited over the mirror surface to create the precision electroformed mold or micromold. Optically smooth nickel molds and micromolds are often produced this way as are mold inserts for CDs and DVD (optical discs), lenses and adaptive optics applications. One way for you to proceed would be to produce the gross shape you want by machining it in wood, plastic or even metal. That basic pattern can then be thinly coated with resin, resist, lacquer or wax to yield the smoothness desired. This precision electroforming for moldmaking and micromoldmaking is an interesting technique you should consider. In addition to macro molds made this way, hybrid molds containing macro features combined with micro and even nano-scale features can be created using advanced precision electroforming technology. We do all this for mold makers and more. Check out www.strictlynano.com

Best of luck!
Sincerely,
Carl Rodia

Check web site www.imsteel.com Click on NAK80 PreHard (hrc40) mold steel that will obtain optical polish faster than any other steel. Also, properly welded, can repolish over weld to perfect match.