The Blacksmith That Mastered Precision Grinding And Sparked The American Engine Boom

In 1826, Stephen Heald lit a forge beside a stream in Barre, Massachusetts, in a settlement so defined by his family's water-powered foundry that locals simply called it Heald Village. For decades it was the only foundry within twenty-five miles, fed by pig iron and coal hauled in by horse and wagon from the nearest railhead. One hundred and sixty-six years later, the company that grew out of that forge closed its doors in Worcester as a division of Cincinnati Milacron, having built the precision grinding machines behind the automobile age, two world wars, and, for five classified days in 1960, the American nuclear weapons program. This documentary follows the Heald Machine Company across all four generations of family ownership. It covers the pivot from farm tools to metalworking under James N. Heald, a Worcester Polytechnic Institute engineer whose American Twist Drill Grinder sold worldwide, and the 1903 move to 10 New Bond Street in Worcester's Greendale neighborhood, next door to the Norton Company's abrasives empire. It examines the 1905 breakthrough that changed manufacturing permanently, the planetary internal grinding machine, patented with Ralph L. Morgan, which kept a heavy engine block stationary while the grinding wheel orbited inside the bore. That single idea became the world's standard method for finishing engine cylinders and remains recognizably intact in machines built a century later. The story continues through the Liberty engine program of the First World War, when five Detroit automakers produced 20,748 aircraft engines whose cylinders depended on internal grinding, and into the interwar innovation streak that produced the Size-Matic and Gage-Matic automatic sizing systems, the Bore-Matic precision boring line trademarked in 1932, and the famous bright-red "Red Head" grinding spindles capable of speeds beyond one hundred thousand revolutions per minute. During the Second World War, the plant ran three shifts around the clock with a workforce the family placed at three thousand, including thousands of newly trained women, and earned the Army-Navy "E" Award for production excellence, an honor granted to roughly five percent of American war plants. Then comes the chapter almost nobody knows. In May 1960, under contract to National Lead of Ohio, operator of the Atomic Energy Commission's Fernald uranium plant, Heald machinists drilled live uranium slugs on their own factory floor during a machine acceptance test. The episode remained buried until the Energy Employees Occupational Illness Compensation Program Act of 2000, when the Department of Labor designated Heald an Atomic Weapons Employer and former workers became eligible for federal compensation. The film also profiles Dr. Robert S. Hahn, the researcher who overturned a century of grinding orthodoxy with Controlled-Force grinding, earned election to the National Academy of Engineering, and continued his research at WPI past his one hundredth birthday, and it traces the 1967 Bore-Matic trademark battle, the 1974 Milacron acquisition, the 1992 closure, and the strange afterlife of Heald machines still running in aerospace production today. Subscribe to Trade Archive for more deep documentaries on the industrial empires that built the modern world. Sources: American Machinist. "Four Metalworking Pioneers Join Machine Tool Hall of Fame." 1998. American Manufacturing Company of Texas v. The Heald Machine Company, 385 F.2d 456 (C.C.P.A. 1967). American Society for Precision Engineering. "Lifetime Achievement Award: Dr. Robert S. Hahn." 1996. Heald, James N., and Ralph L. Morgan. Grinding-Machine. US Patent 810,426, granted January 1906. National Institute for Occupational Safety and Health. Battelle Technical Basis Document TBD-6000, Appendix BD: Heald Machine Co. Naval History and Heritage Command. "Army-Navy 'E' Award." Joint release, December 5, 1945. Northland Tool and Electronics. "Heald Red Head Spindle Repair." Case studies. Pillsbury Funeral Home. "Robert S. Hahn Obituary." January 2021. U.S. Department of Labor. "EEOICPA Covered Facilities: Heald Machine Company." VintageMachinery.org. "Heald Machine Co. History." Reprinting Worcester Magazine, ca. 1909. Worcester Polytechnic Institute. "A Tradition of Research and Development Related to Abrasive Processes at WPI." 2006.