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Can we do localized deanodizing

CAN WE DO LOCALIZED DEANODIZING AS IF WE GO FOR FULL DEANODIZING OF OUR COMPONENT IT EFFECTS OUR REQUIRED DIMENSIONS. IF YES PLEASE TELL THE PROCEDURE.

Jasjeet
EOU - INDIA
2005

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The only way that I can think of would be abrasively, using SiC paper or similar. This, of course, depends on the type of anodising. If it is hard anodising then you are going to be in trouble dimensionally anyway. This method is appropriate for chromic acid anodising and for thinner coatings of sulfuric acid anodising.

I have not heard of a successful method of chemical stripping.

Brian Terry
Aerospace - Yeovil, Somerset, UK
2005

200 gms caustic soda [affil links] to the litre of water.Mask around area to be stripped,works better when extremely hot,paint on surface. Solution reaction increases as anodizing dissolves. Takes a bit of practice but very effective.

D.L.Coleman.
- F.N.Q. Australia.
2005

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2005

Anodizing is easily removed locally by using sodium hydroxide.
However, it will still affect dimensions as it works by digesting the anodizing.
There is no known method for converting aluminum oxide ( the anodized coating) back to aluminum.
However, done properly it is normally more consistent and means less material removal than using abrasives.

Steve Clark
- Belfast, Maine, U.S.A.

You should be able to strip the anodized film from the part without affecting the underlying substrate. A mixture of chromic-phosphoric acid can be used for this. However, this acid mixture is used hot, and you have to mask the rest of the component. You will not reverse the anodized layer back to Al, and there will be a small step between the anodized and stripped areas.

Hassan Ali
- San Jose, California, USA
2005

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Arre baba, just use a 3M tape to mast the area before anodising.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2005