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How to do cadmium plating on deep Cavity area

Hi! All,

This is Karthikeyan from Coimbatore. We are job plating company. we received a job that looks like pen cap. The job is cylindrical having deep cavity depth about 7-8 cm. We are unable to plate inside. Customer wants to do Electroless nickel plating 5±2 Cadmium 16 ± 8 micron thickness. We can achieve inside plating only 30% of cavity area. For this case we expect valuable suggestion from plating expert.

It is challenging order for us.

Karthikeyan P
Employee - Coimbatore, Tamilnadu, India
March 8, 2011

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As you have found out, it is nearly impossible.
The only hope that I can see for the EN is if it is mounted on a rotating rack with the opening facing out from the axis and using excessive fluid agitation and air agitation.
For cadmium, you will have to rack it with a stiff anode in the center of the cavity. Not easy and it is expensive from racking and labor standpoint.
You might want to play around with it with a lab or pilot tank to see what you can do.
Unless you have time and money, I would pass on this job.

James Watts
- Navarre, Florida
March 9, 2011

Depending on the dimensions of the component you could put an internal anode in the center of the cavity. Careful you don't touch the component with the anode. Also increasing the level of sodium hydroxide by a couple of grams per liter would also help.

Mark Lees
- Isle of Man, Great Britain
March 10, 2011

Electroless nickel should be your biggest problem in a blind hole. You need a pump for solution replenishing. For cad plating you just need an auxiliary anode of stainless steel and make sure the hydrogen can escape so mount the part with the hole upwards.

Jeroen Visser
landing gear - Geldrop, Netherlands
March 20, 2011