As the Trump administration works to increase munitions production, precision ball screws have emerged as a critical bottleneck for the U.S. military. These tiny components, essential to Patriot missiles, airplanes, and humanoid robots, can take over a year to produce and cost more than $1,000 apiece. Only a handful of American companies, including Saginaw Precision in Saginaw, Mich., are capable of manufacturing these highly engineered parts. Nick Kolar, executive vice president at Umbragroup, an Italian ball screw maker with a factory in Saginaw, estimated demand has risen 50 percent since 2020. Each missile requires at least four ball screws, which convert rotary motion into linear motion with extreme precision—accuracy measured at roughly one-hundredth the width of a human hair. While common industrial ball screws are readily available, the specialized variants needed for defense applications face long lead times due to limited suppliers and complex production processes involving heat-resistant steel, heat-treating, and chrome plating. Defense contractors like Northrop Grumman and Lockheed Martin already procure these components well in advance to avoid delays. Jeff Kaney, former owner of BGT Aerospace, noted that companies capable of handling tricky orders struggle to meet capacity.

The scarcity of precision ball screws highlights broader challenges facing the American industrial base, where specialized components for weapons systems face extended wait times and limited domestic production capacity.