Enamel for Primed Metal
Randolph Enamel is available in the same 50 colors as Colored Butyrate Dope and Ranthane. Enamel is used only over epoxy primed metal components and, unlike Ranthane, is too brittle be used over fabric. It is normally used to paint the metal parts of airplanes whose fabric components have been painted with Colored Butyrate Dope. Enamel is a close match in color to butyrate dope, but is much glossier and can differ slightly in color from butyrate in the white colors and other light hues. This difference occurs because enamels are made from a light brown resin, while butyrate resin is perfectly clear. Those who want exact color matches in the fabric and metal parts should consider Ranthane polyurethane for the whole aircraft (metal and fabric) or Ranthane over the metal components only. Ranthane is also made from a clear resin, thus the color match with butyrate dope is very close, although like enamel, Ranthane is much glossier than butyrate dope. Aircraft restorers should consider that the classic aircraft of the 30's and 40's were finished in butyrate dope and enamel. They rolled out of the factory with a slight difference in hue and gloss between fabric and metal parts. A true restoration will reflect those slight differences; few antique and classic aircraft had perfectly matched finishes with exactly the same gloss on all components. That "constant gloss" look arrived when polyurethane paints were perfected in the 1960's.
Quarts and gallons only.
One thinned gallon covers approximately 225 square feet with one coat.
Stir thoroughly with a paint paddle, and then shake on a double-action shaker for five minutes.
Mix five parts Randolph enamel with one part 257 Enamel Thinner.
Apply with a spray gun. For best results apply over W-2248 EP-420 Epibond white epoxy primer. Enamel may react with one-part primers like zinc chromate or red iron oxide. Enamel is normally a slow drying paint that can remain tacky for long periods in high humidity. For best results, add 2 ounces of E-9313 Enamel Hardener/Gloss Additive per thinned quart of enamel. This will decrease drying time and increase leveling of the paint for increased gloss. Spray two to three coats twenty minutes to an hour apart.
All coats should be sprayed in the same day, and then set aside to dry. Enamel is an alkyd resin developed with 1930's technology. Unlike today's polyurethane or acrylic paints, delays between coats can result in wrinkling of the enamel surface. This most often occurs when a heavy coat is re-sprayed over earlier applications. For best results, spray two or three coats in one day and consider the job complete. Trim colors of enamel can be applied over a dried enamel base color, but you must wait at least a week and apply trim in light coats, only enough to get the job done. Flooding enamel over enamel will always result in wrinkling.