Question About Oils / Rust Prevention

[Bane]

Hey everyone,

So the specifics of this question are a bit off-topic, but applicable I feel nonetheless. What I'm doing is making jewelry from bits of iron meteorite. I'm putting a quantity of small, sub-BB size fragments of meteorite in tiny glass bottles for use as pendants, earrings, etc. The thing is, the meteorite fragments are mostly iron (not sure of the alloy quantities, but certainly almost 100% iron), and thus will rust over time if not properly protected. Some of the fragments were already slightly rusted when I received them.

So what I need to know is - how do I need to protect these small bits of stardust? I want to make certain that once sealed inside the tiny bottle (with a cork), the fragments will not rust.

So far, I can think of two possible solutions, but I'm not certain how well either will work.

The first solution I can think of is to coat the fragments with a small amount of oil or other rust preventative, although I'm not sure what kind to use. Whatever oil I use, it must not create a film on the inside of the glass, which might obscure the bottle's contents. It also must be colorless, and preferably odorless, or low-odor. I've been toying with the idea of coating the fragments with WD-40, then cleaning most of it off. However, WD-40 has a rather strong odor, which may or may not penetrate the cork over time. Thoughts?

The second solution involves replacing the oxygen inside the bottle with some other gas, since oxidization requires the presence of oxygen. Anyone know how I might accomplish this? Perhaps create a semi-vacuum inside the bottle? We're talking really small bottles here, as in 25mm tall.

Any thoughts or suggestions would be welcome.

Thanks!

~Bane

[Ed Tipton]

Bane...Welcome to the forum. My first thought was WD-40...but you've already thought of that. My second thought, assuming they are rust free, is to spray them with something like clear lacquer. This would be clear, non-corrosive, and would provide some measure of protection after the sale of the jewelry. Possibly baby oil would also work. I don't think that any residue or foul smell would be significant on such a small piece. Personally I think the lacquer idea would be the best. Without some protective coating, they will rust over time.
Just my $.02.

[TexasJack]

Oil is not all that great at rust protection. And some of the components of WD-40 are volatile - leading to the problems you outline.

Wax, on the other hand, can protect the surface. It's not volatile and it doesn't bead up. Museums use Renaissance wax to protect things. Good, cheap, effective, and won't take away from the view.

As for the bottles, you want them both dry and oxygen free, if possible. Corrosion is an electrochemical reaction and water acts as the connection. (Likewise, you should try to make sure you don't leave any oils or salt from your skin on the surface.) Stores and online companies that cater to woodworking hobbyists carry a little can of dry nitrogen that is used to displace air in containers of certain wood finishes so they won't set up between uses. That should fix your problem, again for low-$.

[Bane]

Originally Posted by TexasJack

Oil is not all that great at rust protection. And some of the components of WD-40 are volatile - leading to the problems you outline.

Wax, on the other hand, can protect the surface. It's not volatile and it doesn't bead up. Museums use Renaissance wax to protect things. Good, cheap, effective, and won't take away from the view.

As for the bottles, you want them both dry and oxygen free, if possible. Corrosion is an electrochemical reaction and water acts as the connection. (Likewise, you should try to make sure you don't leave any oils or salt from your skin on the surface.) Stores and online companies that cater to woodworking hobbyists carry a little can of dry nitrogen that is used to displace air in containers of certain wood finishes so they won't set up between uses. That should fix your problem, again for low-$.

Hmm, the wax could work, but I'd have to come up with some way to make sure the pellets are evenly coated. As for the dry nitrogen, I would certainly give it a try if I could find some. So far though, I haven't been able to turn anything up online. Do you happen to know of any websites that carry it? Thanks

[smithy]

Try a product called "Renaissance" wax. It a micro-crystalline wax polish. You can find it at http://www.picreator.co.uk It is pricey, but a little goes a long way and it works great for preventing tarnish.

[Woodchuck Forge]

Bane

another gas option would be argon. Easily obtained at any welding store.

[EdStreet]

This month's issue of Fine woodworking mag has an excellent article on rust prevention, they test 20 different products.

Long story short the resulting top 7 products: CRC industrial 3-36, LPS 3, Moovit, Rust block, WD-40, WD-40 Long-Term Corrosion Inhibitor and 3M Rust Fighter.