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Chromic acid anodise local repair for small areas

I have a problem with a chromic acid anodised assembly to MIL-A-8625 / MIL-PRF-8625 [on DLA] 1B Class I, in which material was removed locally for balancing purposes. I am unable to strip and re-anodise. Is there any way to repair this locally?

Dr Victor Shribman
aero - Tel Aviv, Israel
2005

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Anodizing touch up for type I and type II coatings can be performed using a brush anodizing procedure. Brush anodizing is a process which uses a hand held electrode that will selectively anodize an area without having to submerse it into an anodizing tank. This process will not adversly affect the exisitng anodic coating and is used as a routine repair by the Aerospace industry in this country.

Brush electroplating companies such as ourselves provide either contract plating/anodizing services or systems and training so your technicans can anodize the parts in house or on site if the parts are attached to larger components.

Chris Helwig
- Valencia, California
2005

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First of two simultaneous responses --

Touch up of bare spots with a simple chromate conversion coating is acceptable under the MIL spec. See letter 11001 for details.

Jeffrey Holmes, CEF
Spartanburg, South Carolina

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Second of two simultaneous responses --

Brush anodizing generates heat. Chromic acid anodizing is done at a specific temp. You will need a flow thru system with a tank heater to get it to the desired temperature and then the anodizing will probably generate enough heat to maintain the desired temp in the tank is not too large or too small. Brush touchup never looks the same as the original, but is quite functional. Use a very reputable company to do the work or buy the equipment from a very reputable company that has a formal training program for the operators. Brush anodizing or plating is extremely operator sensitive.

James Watts
- Navarre, Florida
2005
2005