The "recipe" is based on proven principles and incorporates two polar and two nonpolar ingredients. It is adapted from a formula in Hatcher's Notebook, Frankford Arsenal Cleaner No.18, but substituting equivalent modern materials. I had the help of an organic chemist in doing this and we knew there would be no "surprises" The original Hatcher recipe called for equal parts of acetone, turpentine, Pratts Astral Oil and sperm oil, and optionally 200 grams of lanolin added per liter.
Pratts Astral oil was nothing more than acid free, deodorized kerosene. We use K-1 kerosene of the type normally sold for indoor space heaters. An inexpensive, effective substitute for sperm oil is Dexron (II, IIe or III) automatic transmission fluid. Prior to about 1950 that most ATF's were sperm oil based, but during WWII a synthetic was developed for use in precision instruments. With the great demand for automatic transmission autos after WWII, sperm oil was no longer practical to produce ATF in the quantity demanded, so the synthetic material became the basis for the Dexron fluids we know today. The additives in ATFs which include organometallic antioxidants and surfactants, make it highly suitable for our intended purpose.
|