This Screw Is Needed for Missiles and Planes. Buying One Can Take Years.

It’s a spiral carved into metal, attached to a mechanism that might not look out of place in a junk drawer. Almost no one outside a small, obsessive community of machinists and engineers has ever heard of it. But this humble component, called a precision ball screw, is essential to producing Patriot missiles, airplanes and humanoid robots.

As the Trump administration works to replace or upgrade weapons systems depleted by the war in Iran, these screws are in short supply, adding months or even years to the time it takes to make a missile.

“It has created a choke point,” said Nick Kolar, executive vice president of sales for aerospace, defense and space at Umbragroup, an Italian ball screw maker with a factory in Saginaw, Mich. He estimated that demand has increased as much as 50 percent since 2020.

Ball screws are far from the only component of a missile that can be hard to source. Rare-earth magnets, solid rocket motors and high-grade explosives also pose a challenge. But the long lead times on something as seemingly simple as a screw illustrate a festering problem with the American industrial base.

Article source: https://www.nytimes.com/2026/09/26/business/ball-screws-military-production.html