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Can cadmium be reworked selectively

2004

I am the material and process engineer of an aviation manufacturing plant. We have got some parts made from 4130 steel cadminum plated that we need to change their dimensions. This changing shall expose some metal surface.

Is there any manual coating procedure that we can apply in order to repair only the area need to be coated, or that we need to remove the cadmium coating from all the part and re-plating?

Thanks,

Keren Poran-Avrahami
Material and process engineer - Gilon, Misgav, Israel

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Hello Keren,

Yes you can selectively re plate the re worked areas with cadmium using a standard brush electroplating process. Brush plating is a well known and established process for this type of application. For more information, I would invite you to contact a brush plating manufacturer who will help you meet your application requirements.

Chirs Helwig
- Valencia, California, USA
2004

Yes, the part can be masked off and the required surface be brush plated. There are problems with this approach. It is very difficult to not have a different texture where the old plate and the new plate overlap or meet. Brush plating takes a chromate slightly differently than a tank chromate, so there may be an visible difference. It takes a skilled operator to do a very good job and it still may not be accepted by a picky QC inspector. It is labor intensive, i.e., one part at a time. If the part has been removed to be machined, it would quite probably be cheaper and less pain to just strip and replate, especially if there are dozens of parts.

James Watts
- Navarre, Florida
2004