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Tin Sludge on Plating Vats

we recently have heavy sludge precipitation in our tin plating vats. we are using MSA-type tin plating solution. are these sludge inherent from tin anodes or tin solution? although the sludge is not affecting the plating deposition on our substrate, we have not identify a preventive action on sludge. our anodes are conventionally bagged and the tin solution is filtered by HBS-type quad filter design.

Gabriel M. Dial
- Atlanta, Georgia
2000

If nothing else has changed, you might want to see if your filter is inducing oxygen into the bath. It sounds like you are converting your free tin to stannic tin. Also, have you changed to a larger micron filter? You might want to check with the manufacturer of your bath to make sure the filters are of the proper size.

Phil Pace
- Tulsa, Oklahoma
2000

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