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Polishing technique required

I have some punch tips that have been hard chrome plated producing a matte finish. I need to bring this up to a bright mirror finish. Punches are approx. .500 in diameter. Any suggestions as to a polishing sequence to achieve this bright finish. Is this always done with diamond compound?

Cosmo Dattis
- Thorndale, Pennsylvania
2003

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There are certainly things that I haven't' heard of, so just because I haven't heard of it doesn't mean it doesn't exist, but I've never heard of mirror polishing hard chrome. Grinding it, yes; buffing it, yes; but I wasn't aware that it could be mirror polished.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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We have sold a couple of systems to similar companies and the abrasive we recommend and use is a bulky organic wood product. If you need more info, get in touch.

AF Kenton
retired business owner - Hatboro, Pennsylvania
2003

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How thick is the chrome plate? If less than 0.0005" (0.012 mm) you will most surely end up with peeled (exposed) areas. Otherwise, you can try with super fine dry and wet sandpaper. Then high speed rotary nylon brushes and felt w/fine diamond paste.

Good luck,

Guillermo Marrufo
Monterrey, NL, Mexico
2003

G' Day

That good old chrome finish.

I just finished a 3 day site job for a client where the former polisher just didn't achieve a finish on a large mould. I too would have gone the obvious diamond paste solution. What I did find eventually was a combination of 25 micron polish at slow RPM with a small felt disc. Then using 1200, . grade wet & dry. This then gave me the proper base for the final polish using Simichrome ⇦ this on eBay or Amazon [affil links] . It's made in Germany, but can be bought in IOWA. I read that on the tube today when I was packing up. It traveled around the world to give me a solution, now and in the future.

Michael Hein
- Sydney, NSW, Australia
2003

Sorry about the spelling. Polishing hard chrome. When decorative chrome is placed on brass or nickel the finish is under all that called polish metal, if burning occurs in the chrome companies very lightly buff color out the burn. Most polishers push too hard and wipe out the chrome leaven hard to see yellow nickel spot. Hard Chrome should not at all be polished. They mill hardchrome down all evenly, but when buffed your going to get lots of high lows taken away the real reason why you had it hard-chrome in the first place. In decorative chrome has the bright finish and cost about 70% less than hard-chrome.

Russell Charles
- Lawrence, Massachusetts
2003