The firebox, made from an old gas tank, is connected to the grain bin with welded sheet metal.
PHOTO: LOIS OHLSON
A corn dryer is standard equipment on most Midwestern farms, and especially in the state of Minnesota. After all, the "Land of 10,000 Lakes" is famous for its moisture-laden produce, and for its early cold rains and unexpected snow flurries, which make harvesting the crop at the earliest possible date a top priority for Minnesota growers.
Well, Olav Anderson's farm is no exception to the rule. In fact, the at-harvest moisture content of the corn he raises on his 160 acres near Westbrook, Minnesota often runs as high as 25%! And, since grain buyers won't touch his produce until it's been dried down to a moisture content of at most 15% (otherwise, the kernels would spoil rapidly in storage), that Corn Belt farmer knows he must run his crop through a dryer.
However, whereas many folks would be likely to spend $3,000 or more to get a ready-made unit that guzzles costly propane, Mr. Anderson built his own grain dryer from scratch. [EDITOR'S NOTE: The farm equipment source we checked quoted us a price of $9,500 for a 525-bushel-capacity corn dryer, the smallest it had available!] Olav's version not only cost just $65 to make, but also runs on dead wood gleaned off his land. And although he wouldn't mind sharing his plans with MOTHER's readers, Olav says he never really had any. He admits to having looked at a few commercial models at first, just to get a notion of how they're made, but after that he relied on common sense, the materials he could scrounge, and enough time to tinker his way toward a final design.
Anderson's Corn Dryer System
The system is composed of three main parts: a large corn bin, which holds (and moves) the grain while it's being dried, the firebox in front, which receives the material that's burned to create the heat, and a connecting unit, which houses an electric fan used to move the hot air into the bin.
The basis for the dryer's firebox was an old 2,000-gallon gas tank that Mr. Anderson purchased for $25. He cut the used container in half and reshaped it, as shown in the photographs accompanying this article. (That funny-looking "hump" over the box is composed of a couple of 55-gallon barrels that were cluttering up Anderson's yard. The mound's purpose is to catch the last of the warmth before it escapes through the flue.)
Old water heaters, which were too rusted out to serve their original purpose, provided Olav with a chimney. And the draft—which protrudes from the door—is also composed of scrap from a discarded water heater. (Mr. Anderson simply props the draft open with a piece of iron, and claims it does a fine job.)
Olav also used a few steel fence posts to serve as framing for the front portion of the firebox. (They prevent the unit from sagging under its own weight.) Then screen mesh was fastened from the framing pieces to the doors, to keep out trash and residue.
The portals themselves—which are hinged to the framing—were cut from the bottom of the fuel tank. Anderson, who's well over six feet tall, can stand upright in each doorway. The enormous opening allows the farmer to use his tractor and loader to fill the burner with logs, stumps, cornstalks, or just about anything else that will burn.
The firebox holds enough wood to run for eight to ten hours without reloading. The small electric fan, hooked up between the dryer and the corn bin, forces the hot air from the burner through its housing and into the drying area. Another electrical gadget—this one's called a "stir-ator"—keeps the corn moving so that all of the kernels will dry at an even rate.
Anderson's entire system is encased in sheet metal that's been welded together, then coated with plastic roofing cement to prevent rust. Olav also placed the unit on skids so that it could be easily moved.
The Bottom Line
Last fall, the cost-conscious tinkerer tried his invention out. He dried 7,000 bushels of wet corn—while also cleaning out a grove of dead trees—and estimates that he saved more than $700 in the cost of propane alone, with nary a complaint from the grain buyers about the quality of his product!