Hello,  I'd like to add a few things to Mark Singleton's comments
on rusty discs [160707 MMDigest].  As Mark says, "Most of the rust
removing products are chemical cleaning compounds which, apart from
being environmentally unfriendly and probable carcinogens, will
undoubtedly lift the applied factory text."

There is one product that is not an acid and it is also not dangerous
or toxic.  Get thee to an AutoZone or Harbor Freight store and buy
some Evapo-Rust.  It is water based so it won't damage a disc any
more than plain water (or even water with some washing-up liquid).

It's a good idea to get rid of any loose or surface rust first,
although mechanical removal will usually leave a fine coating of
rust.  A soft, brass brush is ideal for the job.  I also find an old
toothbrush quite effective.  I mention an _old_ toothbrush because
I've found that using your wife's toothbrush is frowned upon as the
Evapo-Rust apparently leaves a foul taste in the brush, even if you
rinse it really well.

Soaking a disc in Evapo-Rust doesn't seem to disturb the graphics on
the disc unless you leave it for a long time -- even an hour or so
seems to be okay -- but you should check the graphics on the first disc
now and then to see how long it takes to start loosening the graphics.
If the disc is quite rusty you'll have to decide which is more
important: saving the graphics or removing all the rust.  By the way,
warming the Evapo-Rust makes it work a lot faster.

After the Evapo-Rust has done its job, it's a good idea to apply the
brass brush again to remove the black powder residue and shine up the
surface a little.  I like the furniture polish idea, although I've
never tried it.  The Evapo-Rust itself will inhibit rust for a while
if you let it dry on the surface.  Other things, like spray lacquer
or shellac have been suggested, too.

After you've addressed the problem, please write back and tell us the
results.

Regards,
Craig Smith
Upstate New York

 [ This product is very inexpensive. I was curious what is in Evapo-Rust.
 [ I found: http://www.evapo-rust.com/product-info/technical-info 
 [ Since it leaves a bad taste on a toothbrush, I'm wondering
 [ what the resude is?  Can the residue transfer to the star wheels or
 [ make the discs smell bad? --Jody