Siamese Tractor

Billy Watkins, Moultrie County, Ill., didn’t know at the time, but the spin off effects of his building this Siamese tractor ler to the popular weight transfer sled used at tractor pulls all around the country, and also to a federal landmark decision of the U.S. Patent Office. This photo of Watkin’s tractor, from the C.F. Marley Photo Collection, is just about all that is left of the home-made Siamese tractor. It was another example of “necessity” being the “mother of invention”. Back in the Spring of 1962, Watkins was farming 348 acres of heavy black land. Those were Spring plowing days, and he was faced with a wet Spring. Like other farmers who sought more power with tandems and even triples, Watkins knew he had to do something and do it in short order. He decided on two engines for one tractor and got the job done in 4 weeks. He used the chassis of an old IHC F-30. He salvaged Chrysler industrial engines and transmissions from 21-A Massey Harris combines. To transmit power to the F-30 rear end, Watkins put gears on both transmissions and tied them together with a roller chain. Watkins says his Siamese tractor “worked great.” He used it as his main power source for 5 years, pulling a 5-bottom plow and also a multiple planting hitch made up of a field cultivator, a harrow, and a planter. Servicing the two engines was not as much a problem as you might suspect. The Chrysler engines were L head equipped, and this gave him head and arm room above them. Watkins points out that both engines had clutches, and this enabled him to run them together or separately. For plowing ends, for example, he merely shut one engine off. Where is the tractor today? “Over in the junkyard,” he reports. “Tractor pullers have scrounged some of the gears off of it, and they are still in use.” Soon after he built it, Watkins entered his Siamese tractor in pulling contests and caught the “pulling” fever. Once he got his tractor into pulling, he became concerned about how dangerous it was to have men step on and ride the sleds, which was state of the art in those days. Necessity being the mother of invention once again, Watkins designed the weight transfer machine (as it is known, officially). He also filed it for patent. Soon, Watkins noted his weight transfer machine was being copied, but builders were ignoring his patent rights. He sent letters to copiers, asking for license fees. This annoyed the copiers and they had the the National Tractor Pullers Association sue Watkins for harassment. Watkins filed for a countersuit and won. The decision rendered has become a landmark case, the first to use “re-issuance”. Watkins says there is a lot of interest in the re-issuance procedure and that his lawyer gets calls from all over the country on how it works on a wide variety of patents, including many not even related to tractors or tractor pulling.

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