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Corrosion protection of machined aluminum parts

I am looking for a spray on product to use to protect machined aluminum parts from corrosion after they have come off the machines but before they have been through the burr shop and go on to outside processing. These are specifically aircraft parts, mostly of the 7000 series of aluminum. Airframe structural components and wing skins. We currently use Panther Protectol S in a 40-1 mixture. We have had some instances of failure after applying it, the parts will still corrode.

Stuart Countryman
- Wellington, Kansas, USA
2003

Are you using an aqueous cutting fluid? Make sure to use a cutting fluid suitable for non-ferrous metals; I have seen high pH cutting fluids corrode anodized aluminum machine parts. Significant chloride in tapwater increases the corrosion.

If electrochemical machined parts are corroding, try better rinsing and blowing off the water with an air-knife before applying the preservative.

Hope this helps,

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2003