Why Stainless Bolts Gall

Q: Why do stainless steel bolts seize?

Stainless bolts can gall—cold-weld and tear—when similar metals rub under load. Friction and lack of lubrication cause the surfaces to stick and tear.

Q: How do you prevent thread galling?

Use anti-seize or moly paste, avoid overtightening, use different grades (e.g. nut and bolt from different stainless families), and start threads by hand.

Q: Can you reuse a galled bolt?

Often no. Galled threads are damaged. Replace the bolt and nut and use lubrication or anti-seize on reassembly.

Why stainless steel bolts seize, what thread galling is, and how to prevent galling when using stainless fasteners.

What is thread galling?

Galling is when two similar metal surfaces (especially stainless) cold-weld under friction and load. Threads can lock together, tear, or seize. Stainless steel is prone because it work-hardens and has a tendency to adhere when lubricant is absent. Correct assembly and lubrication greatly reduce the risk.

Why stainless bolts lock up

Similar alloys (e.g. 304 on 304) rubbing under load
Dry threads and high clamping force
Overtightening or cross-threading
Soft oxide layer breaking down and metal-to-metal contact

How to prevent galling

Method	Notes
Anti-seize or moly paste	Reduces friction and adhesion
Different materials	e.g. bronze nut on stainless bolt
Hand-start threads	Avoid cross-threading
Correct torque	Use a torque calculator; don’t over-tighten

FAQ

Why do stainless steel bolts seize?

They can gall—cold-weld and tear—when similar metals rub under load without lubrication.

How do you prevent thread galling?

Use anti-seize or moly paste, avoid overtightening, mix materials where possible, and start threads by hand.

Can you reuse a galled bolt?

Usually not. Replace the fastener and use lubrication or anti-seize on reassembly.