The big one: buy the right grade for the environment (316 near salt, 304 elsewhere). After that, rust prevention is mostly about avoiding contamination, mixing metals, and trapped moisture.
1. Buy the right grade
No maintenance saves an under-specified hinge. 304 near the coast will stain no matter how clean you keep it. Match the grade to the exposure first — everything else is secondary.
2. Don't mix metals
Pairing stainless hinges with carbon-steel screws (or aluminum hardware) sets up galvanic corrosion in damp conditions: one metal corrodes to protect the other. Use matching stainless fasteners — ideally the same grade.
3. Avoid carbon-steel contamination
Grinding dust, steel wool, or a carbon-steel blade can embed tiny iron particles in stainless. Those particles rust and make it look like the stainless failed. Keep stainless away from carbon-steel tooling, and never clean it with steel wool.
4. Rinse off salt
For coastal hardware, an occasional freshwater rinse removes the salt deposits that drive tea staining. It is the highest-value five minutes you can spend on marine hardware.
5. Keep it clean and dry where possible
Wipe off grime and standing water. Trapped moisture in crevices is where crevice corrosion starts. A mild soap-and-water clean a couple of times a year is plenty for most hardware.
6. Lubricate the pin, not the finish
A drop of light oil on the pin keeps the hinge swinging and displaces water at the wear point. Don't slather oil on the leaves — it just collects dust.
7. Consider passivation for critical parts
Passivation is a treatment that strengthens the passive layer by removing surface iron. It is overkill for most homeowners but worth knowing about for demanding industrial installs.
Frequently asked questions
Why is my 'stainless' hinge rusting?
Three usual suspects: it is actually a lower grade than advertised, it was contaminated by carbon-steel particles, or it is 304 in a salt environment that needed 316.
Do stainless hinges need oiling?
Only the pin, and only for smooth action. The corrosion resistance comes from the alloy, not from oil.