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Alternative coating to zinc (cost effective)

2004

I wish to prevent a steel component from rust (storage not external use) and have tried zinc plating (yellow and bright). I have 2 problems, first there seems to be a reaction with a phosphate bonded potting compound which coats part of the steel tube. Secondly I am thinking about welding a part to the tube but am concerned about toxic fumes.

Because zinc seems unsuitable I have tried a black coating which I was told was carbon black, although I suspect is some kind of etching in a hot bath. Do you have any suggestions for a solution, or the best solution for a protective coating suitable for welding and use with phosphate bonded cements?

MANY THANKS

James Yardy
thermocouples for molten metal - Sheffield, Yorkshire, UK

To prevent metal from corrosion at cheaper costs, you might be able to get asphalt, asphaltene I believe is one of corrosion coating product, but how to dilute the asphalt to become liquidize, you can try with tce, but cheaper if use Xylene ⇦ this on eBay or Amazon [affil links] , until you find a viz level you wish. Okay, good luck

Daniel Herman S Suhendra,drs
dp minchem int - Jakarta, Indonesia
2004

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You might try E-coat. Depending on how long your tubes are you can get really good coverage. With the immersion tanks you can get about 15 inches throwpower from each hole. Its a thought right?

Curt James
- Arlington, Washington, USA
2004

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You can use 2o gm tannic acid ⇦ this on eBay or Amazon [affil links] /15 gm phosphoric acid /1 lit water solution,after this process you must lacquer, cheap paint is 2oo gm shellac/1 lit pure alcohol, mix it with iron oxide black pigment.

Good luck!

Goran Budija
- Cerovski vrh Croatia
2004