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Tin plate of 12L14

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I am having a problem with pitting of 12L14 after tin plating.

Stephen Gallen
- Glenolden, Pennsylvania, USA

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OK- Are you just telling the world you have a pitting problem or do you have a Question. More information is required if you have a question, like what is the exact question? with details!

James Watts
- Navarre, Florida

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Stephen, 12L14 is a free machining steel- it has controlled amounts of 'dirt' in the steel to aid machining, in that the chips break easier. This 'dirt' will likely give you fits should you want to put a pit-free thin coating on the part. Make sure your coater knows the material- perhaps they can do some additional preparation or put on a thicker coating.

Good luck!

Lee Gearhart metallurgist East Aurora, New York

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12LXX is a "leaded steel" and little flakes of lead can be seen on the surface with a magnifying glass. Lead forms insoluble salts with sulfates, chlorides and many other acids, however, lead does not form an insoluble with Fluoboric Acid, therefore skip the sulfate acid salts, skip the sulfuric acid, skip the Hydrochloric acid and run your parts through 30%/vol Fluoboric Acid before plating.

Robert H Probert Robert H Probert Technical Services Garner, North Carolina Editor's note:        Mr. Probert is the    author of Aluminum How-To / Aluminio El Como