In 1972 Machine Design magazine held the one of the first mouse trap powered car contests. There were 94 entrants from several countries competing.
It took about six months for my father, Dr. Frank Kinsman, to build this car which took first place and actually brought home both trophies from the contest- maximum distance and maximum economy. This car went 825.30 feet and weighed 1.72 ounces (48.9 grams). Allowed materials were the parts from a Victor 4-way mousetrap, a composite wood material trade named Masonite, epoxy, string, piano wire, and lubricants. Each photograph includes a quarter for size comparison. The plastic stand is only used to support the vehicle for display purposes.
Interesting design and manufacturing stories- The large wheels were machined side by side on an antique 1905 machine treadle lathe. This insured they were exactly the same diameter and would therefore track straight. The spokes were airfoiled and finally the wheels were balanced on razor blades. The energy from the spring powered a fusee and a collection of gears machined out of Masonite. One interesting note the Mattel toy makers told us after the contest was that if the spring were unwound, hammered flat like a clock spring, and wound up again it would store approximately 3 times as much energy as it could in the 'stock' state.
Frank B. Kieser of GE Space Division knew this trick and produced a car that went 751.4
feet. Most observers agreed that his car would have easily won if it had been geared just
a bit higher. The fact that it took off like a rocket pointed to too much energy being
consumed in acceleration. This was a race for distance not speed.
William, my son, was required to build mouse trap powered car in 2004 for a school project. Family
tradition dictated that it must have only two wheels. Ridiculed by both teachers and students for
a vehicle that could not possibly work, he proudly launched his pulley only vehicle which
travelled approximately three times the distance any other student achieved:-)