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  for Metal Finishing since 1989
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Electro Galvanized plating questions

2001

Hello everyone,

Before anything please excuse my lack of knowledge in the plating field. A quick response to my following question will be most appreciated. Could someone explain the pro and cons of using pre-plated material (i.e. EG) instead of post-plated if the environment at which this material would be exposed will be humid, hot, and possibly close to the sea.

Thank you!

Best Regards,

Luis Aguirre
- San Jose, California, USA

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Preplate material is fine, until you cut holes in it! Any punching or cutting leaves areas without any plating and therefore no corrosion resistance. Preplate is used quite often in computer assemblies that operate in climate controlled conditions.Exposure to a moist, salty environment would require a good, even coverage of some highly resistant coating.You are fortunate to be in an area of California that offers an assortment of metal finishing shops that can assist you in your needs.

Good luck,

Bill Grayson
- Santa Cruz, California, USA
2001

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Pre-plated material is almost always less expensive, and that is the principal reason for pre-plating. Depending on the final shape of the part it is also possible that pre-plating will give more consistent thickness. The advantage of post plating is both decorative and functional. Pre-plated material has sheared edges which are not plated, and which, depending upon a lot of "ifs, ands, and buts" can obviously therefore rust prematurely.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2001