McCay Tool and Engineering

Founded in 1950, McCay Tool and Engineering is a defense contract manufacturer based in St. Louis, United States working in air systems, missiles & munitions, mro & logistics.

McCay Tool and Engineering is a St. Louis-based contract manufacturer founded in 1950, specialising in precision machining, sheet metal fabrication, welding, assembly and aerospace component production. The company traces its origins to post-World War II government contract manufacturing and is reported to have produced warheads for Raytheon-built Patriot missiles under a U.S. Department of Defense contract in the late 1980s. Its customers include Boeing, Lockheed Martin and the U.S. government and allied governments. Capabilities include 3-, 4- and 5-axis CNC milling, CNC turning, cylindrical grinding, welding of defense assemblies, composite part fabrication and FAA/EASA Part 145 maintenance, repair and overhaul services for aircraft and rotorcraft. The company is ISO 9001 and AS9100 certified and follows Boeing and Mil-Spec welding standards. In 2022 it was acquired by Aero Solutions and Technologies, backed by Partners 4 Growth. The company is headquartered in the Evergreen Industrial Drive area of St. Louis, Missouri.