[masraum]

WOW! So it's basically just a huge, heavy safe, but with very high tolerances.

I'd say the way to go is reverse electrolysis which is what lots of folks use when restoring rusty old tools, but thats too big and too heavy.

I feel like a solution that should work would be sanding with a very fine grit wet/dry sandpaper. Rather than using water (the norm when wet sanding), I'd use something like Windex (often used when sharpening tools like plane blades and chisels) or a cutting oil, like the oil used in some sharpening systems (like Lansky). I'd probably use the sand paper in conjunction with a block or curved surface to help keep things flat.

Sanding should get you a smooth surface (better than steel wool or a wire brush, I would think).

And then immediately afterwards, a light coat of either oil or wax (wax is often used to protect old tools, but oil should also work).