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Old 02-21-07, 03:33 AM
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DannoXYZ 
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Originally Posted by cs1
Thanks for the replies. I can't remember exactly who recomended against chrome plating. I do know they mentioned hydrogen embrittlement. I've always had a soft spot for chrome plated bicycles. Nothing looks better than a chrome plated Paramount. Seeing as the frame was a Waterford, I figured I was half way there.
Chrome-plating requires three layers, copper, tin and chrome for best adhesion. To prepare the bare-metal for the first layer, commercial-strength hydrochloric or sulphuric acid is typically used. The strongly dissociated hydrogen causes embrittlement in the metal; you'll want to have thick enough tubing to account for some loss of strength.

The final layer is added using chromic acid H2CrO4 - "hexavalent chromium". Spill a single beaker of this stuff and you'll need to evaluate an entire city block around the place.

Basically, the strongly acidic and toxic chemicals used in chrome-plating weakens the metal. Cad-plating is a quick, fast & cheap way to prevent rust on untreated steel. It's done through an electrolytic dip in a cadmium-salt solution, no acids to worry about...
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