Threshing with Horses

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The threshing machine. Straw is fed in one end, grain is threshed and drops to the canvas below and most of the straw is spewed out the back.
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Grain scooped from the canvas will be cleaned in the fanning mill.
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Tim Calvin working with his family’s horse-powered treadmill belted to a threshing machine.
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Grain is poured into the fanning mill, which separates out chaff and straw.
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The burr mill is used to grind wheat into flour and separate out the bran.
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Wire tying is a low-down job, but someone has to do it.

Looking for an adventure? Step back in time to the late 19th century at the Miami Valley Steam Threshers show.

You’ll see the Calvin family of Radnor, Ohio, with its horse-powered equipment at Past Time Park in Plain City, Ohio, demonstrating how wheat harvesting used to be done.

Using equipment from the late 1800s and early 1900s, the Calvins “thrash” wheat, winnow grain and grind it into flour, and bale straw – almost all with horses. They use a pair of horses, not a team: The two animals are never harnessed together to work as a team. One works the treadmill for the threshing machine while one rests. When it’s time to bale, the other operates the “power” for the hay press. The only concession the family makes to the internal combustion engine is a 1-cylinder McCormick hit-and-miss engine used to power the burr mill.

The thresher had its beginnings in Europe as the Industrial Revolution spread to agriculture. American-made threshers began to come on the scene in the 1830s. Before the close of the century, steam power ruled the threshing world. Some of us who grew up in the 20th century are familiar with the big threshing machine powered by a steam traction engine or a gas tractor. Both are large machines and are frequently demonstrated at antique farm equipment shows. Few shows feature the novelty of horse-powered threshing equipment in action.

The Calvins’ thresher is a unique machine that does nothing more than thresh the grain. It does a fair job of separating straw from grain but it does not winnow the chaff, dirt and short straws from the grain. Instead, grain and debris are simply dropped on a canvas beneath the thresher. The accumulated grain, chaff and bits of straw must be cleaned before it can be used.

In the early years, horses were used to power threshers. Some horse power units were treadmills; others were powered by a sweep. The Calvins use a treadmill to operate their thresher. Their treadmill’s endless belt consists of wooden slats with rollers at each end. The belt and rollers are housed in a sturdy frame enclosed by a stall to keep the horse in place. The entire contraption is inclined so that when the horse enters the stall and the brake is released, the horse’s weight causes the belt to slide backward. To keep up, the horse begins walking up the incline, which keeps the belt moving during the threshing operation. At the lower end of the treadmill is a power shaft with a pulley on it. As the pulley turns, the belt propels the threshing mechanism.

When the canvas beneath the thresher is filled, the horse is stopped, the brake is set on the treadmill and the horse is backed out and tied to a tree to rest. Now the chaff and straw are winnowed from the grain. The Calvins use a hand-crank fanning mill, a wooden box with several wooden paddles attached to a rod geared to the crank. Several screens are enclosed in the box. As grain is poured into the machine and the crank is turned, the flow of air generated by the turning fan blades blows across the screens. Grain falls into the screens and is sifted to the bottom as loose straw and chaff blow away.

When the run is complete, the clean grain is ready for the burr mill. This handy device grinds the grain into flour and separates the bran. The quality of the flour produced is determined by the distance between the burrs (revolving abrasive surfaces). As grain is fed into the mill, it is finely ground. Screens separate the fine powder (flour) from the more coarse material (bran) and the flour is bagged.

One more job remains: baling the straw. The Calvins’ hay press is a simple machine operated by at least three people. One feeds straw into the receiving box. One helps feed straw and pokes and ties wires. The third leads the horse in a circle to provide power for the press.

As the feeder fills the receiving box with straw, the plunger forces the straw into the bale chamber and the ram packs it tight. When the appropriate bale size is attained, the feeder inserts a slotted wood block to receive two wires. The block marks the end of one bale and the beginning of the next. When the block moves backward in the bale chamber, the wireman goes to the off side and pokes one end of the wire through the block, then walks to the other side, pulls the wire through and ties it off. Then he pokes the wire through the block for the next bale. After the bale is forced out of the machine, the wireman builds a stack of finished bales.

The hay press is powered by a power sweep. The Calvins’ 1-horse sweep consists of a center post with one beam radiating out. The horse is hitched to the beam and walks in a circle, causing the center post to rotate a large geared wheel. That drives a pinion and shaft. A pulley and belt can be attached to the shaft, or the shaft can be connected directly to the hay press in the same way as a PTO shaft.

If you are ever in the mood to travel back in time, do it when the Miami Valley Steam Threshers host their annual show in Plain City. The Calvins set up there every year, giving an idea of what life may have been like on the farm in the late 19th century. It’s hot and dusty, and sometimes it rains, but it’s always fun to watch. FC

Click here to see a horse-powered treadmill in action. You can also find the video by visiting Farm Collector‘s video index, clicking on the Featured in Farm Collector playlist and choosing “Horse-powered Treadmill.”

For more information:
– The Calvins hold shows at their Ottowa Bota Farm. Contact Tim or Walter (Pop) Calvin, 7585 Taway Rd., Radnor, OH 43066; (740) 494-4200;
– Miami Valley Steam Threshers Assn.: Contact Gary Gallimore, 445 S. Main St., West Mansfield, OH 43358; (614) 296-5814; e-mail:;

James N. Boblenz grew up on a farm near New Bloomington, Ohio. He now lives in Marion, Ohio, and is interested in antique farm equipment, particularly rare and lesser-known tractors and related items. E-mail him at

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