Castor Oil By James Goss      As you probably already know castor oil is used in a large percentage of our model fuels. It is said to be better than synthetic oil because it will flash at a higher temperature than will the synthetic oil. This means that it will not burn away if your engine over heats as readily as the synthetic will. If the oil is burned away while your engine is running, you have nothing to lubricate the moving parts, such as the piston, rod bearings, and ball bearings. The engine will seize up and be destroyed. In other words you have “fried your engine”. Caster oil is one of the few natural oils that can withstand this kind of heat so it has become an icon in the model engine field. Of course it does have some disadvantages. We all know how hard it is to clean up the residue on our planes after an engine run. Just think what it would be like if we used 100% caster oil in our fuel, like in the old days. Some modelers still do use 100% castor for its superior lubrication. We joke about getting our wife to clean up our planes after we fly them, but with all caster you probably would be asking your wife for help.      Castor oil comes from the castor bean that is produced by the castor plant. Compounds of the oil are essential for making high-quality lubricants for heavy equipment and jet engines. Caster oil is also used in paints, coatings, plastics, antifungal compounds, shampoo, cosmetics, and many other industrial products. So our model engine usage is only a small part of the total consumption of caster oil that is used in the United States and all over the world. I bet you didn't know this! Inside the beans of the caster plant is a toxin that is seven times more deadly than cobra venom. Known as ricin, the compound's toxicity is one reason why the American farmer is no longer growing this crop extensively, even though a lucrative market exists for the castor bean's unique oil.         Besides the ricin toxin, there's another reason why this crop has fallen out of favor with U.S. growers. People that work with the white meal ground from castor beans tend to have problems with hives and asthma. Some have had fatal experiences with these reactions. Castor is a semitropical plant that thrives in sunny climates. In the U.S. castor is harvested annually when the plant it is about 4 or 5 feet tall. They get about 1000-lbs of oil per acre. Most of the castor oil you have in your model fuel comes from India.  Even though the oil is said to not have the ricin toxin in it, who knows, they may be wrong. I would hate to be bitten by seven cobra snakes at the same time. One thing is for sure, castor oil really don't taste that good, as I recall from my younger days.