The problem is with the different materials that compose the weapons. Can’t talk about wood, as I don’t know enough about it. Ian’s numbers, for the material he describes, make sense to me, for what is worth. However, this level of humidity is far too high for metals. In fact, anything higher than 50% RH is definitely risky for things like bronze, brass and steel. And I'm stretching it. I would feel more comfortable recommending indeed 30-40%, but this would be too dry for many woods and organics (leather, textiles...). I think 40-50% is a good compromise. If this can't be reached or it's still too dry for some materials, remember that physical barriers help a lot in isolating the metal from the environment. Thin mineral oil, nitrocellulose lacquer or, even better, microcrystalline wax may work wonders with your blades and fittings.
Another thing: dust is bad. It increases the chance of the humidity actually condensing in the surface of the metal, so if you can't encase the weapons at least keep them as dust-free as possible.
|