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Chrome plating problems on Tenzaloy

2004

We are attempting to provide our customer with bright chrome plating on marine chair pedestals that are made of a cast tenzaloy base with a 6061 extruded tube press fit into the base but we are running into two problems.

1: The base exhibits a large amount of porosity after surface prep which consists of sanding the base in several steps. It takes a high thickness of copper plate and several buffing operations to cover the porosity making the part too expensive for the customer.

Is there something we, the platers, can do to fill the porosity or can anyone suggest a better material to cast the bases with that has low porosity?

2: The plating on the base sometimes developes blistering. This blistering can appear shortly after plating or in some cases weeks after the plating is completed. We have tried baking the parts at 375 for 1-2 hours to attempt to outgas the casting but it does not seem to help. We are not the only ones experiencing this problem. The powder coaters our customer uses also see this.

Are we not baking the part long enough? Is the temperature too low? Is it a combination of both or is this just the nature of the cast material?

Tim Hamlett, CEF
- West Palm Beach, Florida, USA

If you are using acid copper to build up, and polishing, there really isn't anything you can do other than making the product with a different raw material that is not so porous.

Eddie
- Kiss, Florida, USA
2005

Ed. note: full name please, Eddie. Sorry, we can't print your further comments without your full name.

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If, after all that, the base if porous, you probably need vacuum impregnation before plating, Tim. Good luck.

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