Hello all

I have used citric acid quite a bit to remove rust etc from steel, without problems.

The two attached pictures are of two hand wheels that I've had laying about that were chromed and I wanted to get rid of the chrome, so I put it in citric acid.

At about the same time, I put some big green shed hinges and steel wheeled castors in a separate container with citric acid. They were both left in the citric longer than I intended.

Both containers have formed a yellow scale on the steel and yellow sludge in the bucket. The hand wheel bucket is worse than the hinges etc.

The scale is VERY hard on the hinges and difficult, but not impossible, to remove, with no apparent damage to the steel underneath.

Any idea what the scale is and is it harmful to me? Suggestions on the best way to remove it and stop it from occurring again?

Thanks in advance.
Attached Images




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