Letter 2130

Stripping Dry Film Lube from anodize

-- How do you chemically remove Dry Film Lube from Hard Anodize? Garry Pickett aerospace - Los Angeles, California -- The best way that I have found is to dry blast with shell media such as walnut and etc. It seems to adsorb the dry film as it gently abrades. Works better than careful glass bead. James Watts - Fl -- Garry, I am not sure if you want to remove dry film lub alone without damaging anodic coating or whole anodic coating without damaging substrate material. In the former case, you probably need to develop a chemical solution which is able to oxidize insoluble dry film lub into soluble species. In the latter case, the general stripping solution (20g/L chromic acid plus 35ml/L 85% phosphoric acid at 200-210 F degree for 10 to 20 minutes depending on the coating thickness) is probably suitable to your application. Good luck. Ling Ling Hao - Grand Rapids, Michigan

-- An air dried or improperly cured oven baked dry film can be removed with MEK / methyl ethyl ketone [link is to product info at Amazon]. A boiling solution of 20% chromic acid has been reported to strip dry film. However, in our experience it only softens it slightly and attacks the base anodize. Mechanical methods, such as abrasive blasting or wire brush, are the only sure-fire removal methods. Of course, great care must be taken not to damage the substrate. Chris Jurey Luke Engineering & Mfg. Co. Inc. Wadsworth, OH -- Gary, You can strip dry film lubricant from anodised aluminium etc using proprietary products based on concentrated Suplhuric acid e,g Ardrox 29 or Turco FR. Immersion times are typically 1 hour at room temperature. This process is normally followed by neutralisation in Sodium Metasilicate solution and a cold water rinse etc. The details are normally provided by the chemical companies. Hope this is of some use. In my experience it does not damage anodised films. Stuart Cox