B. McCaw

OVER THE PAST 30 years of model building, there have been many materials introduced for covering and finishing models. The most popular and easiest to finish at the time I became an active modeler was Silkspan (like tea-bag paper). For larger models, one used silk. Dope was the only finish used then. The period was 1948. Up to that time, nitrate dope sufficed because models used either gasoline ignition or diesel engines, or were rubber powered. When Ray Arden introduced the glow plug engine in the late 1940's, the now familiar glow fuel containing alcohol and nitromethane came into being. Nitrate dope was no longer suitable so we began to use butyrate dope. Butyrate dope is used on full scale fabric-covered aircraft because it is fire resistant while nitrate dope is not. It has the virtue of being hot "fuel proof," or more appropriately, hot fuel resistant.