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Dissolving Tin Anodes FAST

We are Electroplating Tin on Brass Parts in a barrel operation to a thickness of 2-3 microns (metric). The anodes are pure Tin Slabs and they dissolve extremely fast, compared with our other processes, Is this dissolving rate is normal? We process approximately 3,000 kg of parts and use 60 kg of Tin.

Thanks for your help,

Enrique Segovia
- Monterrey, Mexico
2003

You did not say which type of electrolyte you are using for your tin plate. If it is alkaline, you may wish to investigate "high speed" anodes (containing 1% aluminum).

In any case, whenever we plate tin on brass, we like to use a barrier deposit such as copper or nickel (0.0003"). This prevents zinc migration from the brass into the tin deposit.

Finally, if you can measure a part and weigh it, you can calculate more closely the surface area per load. Some parts have incredible surface areas, and can consume more tin than we would guess at first observation.

Ed Budman [dec]
- Pennsylvania
With deep sadness we advise that our good friend Ed passed away Nov. 24, 2018
2003

Edward,

Thanks for your reply. I didn't mention that we are using a Bright Acid Tin Bath, containing mainly sulfuric Acid and Stannous sulphate with proprietary brighteners, we run at a temperature of 25-30 °C (we have to cool the solution) to maintain this temperature. I'm going to calculate area and also weight based on thickness to determine if we are applying so much Tin, but like I said before, our other processes consume maybe 10 times less metal.

Thanks again for your help,

Enrique Segovia
- Monterrey, Mexico
2003