He also produced a threshing machine, a clover sheller of stone, a blacksmith's bellows and a hill-side plow. He eventually decided to formalize some of his work when he applied for a patent in 1830 for a 'hemp-break', a device for breaking hemp and flax. By 1809, McCormick had constructed a partially completed reaper. He frequently busied himself with small gadgets and inventions around the farm. McCormick and his wife Polly raised their eight children on the farm who grew up helping in the shop and the mill. : 117 His paternal grandparents were Thomas (1702–1762) and Elizabeth ( née Carruth) McCormick, Presbyterian immigrants born in County Londonderry and County Antrim, Ireland respectively who married in 1728 and settled in Cumberland County, Pennsylvania in 1735. McCormick's maternal grandparents were Scottish immigrants, George Sanderson and Catharine (née Ross) Sanderson.

had five elder siblings: George, Martha, Elizabeth, William, and James. His parents were Revolutionary War veteran Robert McCormick Sr. McCormick was born June 8, 1780, on the family estate of Walnut Grove in Rockbridge County, Virginia, in the Shenandoah Valley on the western side of the Blue Ridge Mountains. Although he lived his life in rural Virginia, he was patriarch of the McCormick family that became influential throughout the world, especially in large cities such as Chicago, Washington, D.C., and New York City.

(J– July 4, 1846) was an American inventor who invented numerous devices including a version of the reaper which his eldest son Cyrus McCormick patented in 1834.

Mccormick reaper 1845