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Q&As since 1989


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Possible to chrome an aluminum casting?

I was wondering if it is possible to chrome plate an aluminum sand casting or plaster casting and what kind of finish can be expected? What would I need to look for in casting quality?

Judd Collins
hobbyist - Martinez, California, USA
2007

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1st of three simultaneous replies --

If this is a one-only project, make your life easier, cast it in bronze or at least in Zamak. A single aluminum casting will prove to be an absolute headache to have it plated properly. If you are thinking of medium volumes, shop only among the best aluminum casters and platers and still expect a lot of defects. For high volumes, a permanent steel mold will prove to be a wise investment. Guillermo Marrufo-Mexico

Guillermo Marrufo
Monterrey, NL, Mexico
2007

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2nd of three simultaneous replies -- 2007

Sure it is. Look at all those chrome plated aluminum wheels on new cars.

You'll need castings which are free from porosity. Pressure cast is best.

Jeffrey Holmes, CEF
Spartanburg, South Carolina

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3rd of three simultaneous replies -- 2007

We can plate aluminum sand castings. The quality is largely based on the quality of the casting. The more pits in it, the more pits will show up in the plating. We can plate the parts with a heavy acid core copper and then buff the copper pushing the copper into the pits. The quality trying to be achieved will determine how many times it will have to be acid core copper plated and buffed.
After the desired finish is achieved it will be nickel plated then chrome plated for the final finish.
Eliminating all the pits can be very time consuming and sometimes not completely effective. It is largely based upon having as few pits as possible and the pits as small as possible.
Best Regards, Frank

Frank DeGuire
- St. Louis, Missouri, USA