NewSaurus

Tips

• If the disc is an Xbox 360 game, attempt to return it for an exchange. Your mileage may vary, but Microsoft saved about 25¢ on the build cost of the Xbox 360 by not including safety measures which would prevent a lot of scratches. Most stores have deals worked out with the distributors to where they can get credit for damaged discs, but only discs that were damaged inside the 360. Such discs will have deep radial scratches, sometimes not around the entire circumference of the disc. It could not hurt to try. (Try a few stores actually; the worst they can do is say no.)
• The polycarbonate bottom layer of the disk acts as a lens, which focuses a larger patch of laser light down to a smaller size needed to see the track on the data layer. This lets the laser look through some small imperfections on the plastic surface which are much larger than the track on the data layer. Removing a lot of plastic can affect the refractive property of the lens making the data unreadable. This means that even a visibly scuffed or spider-web of scratches may play well because, though the defects are visible to your eye, the laser sees around/through them. This is why waxing can help. A repair does not have to look perfectly polished to work.
• Deep gouges are not repairable. However, because of the way redundancy is used in the data on the disc and the way the data are distributed along the spiral track, cleaning a disc area away from a scratch can improve data recovery; a number of smaller defects distributed along the track can be as bad or worse than one larger defect.
• It is a good idea to create a backup of any data disc before damage occurs.
• If it still does not work after you tried everything, use it as a coaster for your beverages.
• A number of CD cleaning and repair kits are available for sale, but many users report that these do not work any better than Brasso, and they’re far more expensive.
• With Xbox 360 discs, if you use one of the temporary methods, you can install the game to the hard drive by going to the game library, clicking on the game, then install game. This doesn't always work, as the Xbox has to access the disc to verify it as legitimate.
• Practice repairing scratched CD's that you do not care much about before you set out to repair your favorites.
• You can buy a disc scratch remover from most game stores. It works for all types of CD's with a light level of scratches.
• To remove deep or stubborn scratches quickly, try using a dry "Mr. Clean Magic Eraser". This is a sponge impregnated with a micro abrasive. Use light pressure, wiping from the center of the disk to the outside edge just as described with other polishing methods. The repaired area can be buffed until shiny using the other polishing or waxing techniques described.
• If a CD is scratched but continues to play correctly, make a backup, but do not bother trying to repair it yet.
• Tracks on a musical CD go from the inside to the outside of the disc. Thus, scratches in the shape of a concentric circle causes the most damage due to the interruption of many consecutive data bits. This means that the Reed-Solomon error correction algorithm could fail to apply guesses and generate the missing data.
• Use a quality CD drive from a desktop computer. If you are trying to read a dual layer disc or scratched disc with a front loaded (slip in) CD drive, you can pretty much forget about getting a good read. These drives are notorious for having poorly calibrated/calibrating lasers and are practical useless for anything but brand new CD's. This has been documented by many a repair technician.
• Severely damaged CDs may not be repairable. Very deep scratches and cracks that reach the CD's foil may render a CD forever useless. It does not take much to damage a CD. As a matter of fact, the Disc Eraser utilizes this principle to render CD's and DVD's unreadable, which is useful to have if you want to get rid of sensitive discs.
• If all else fails, you could always take it to your nearest video/gaming store to repair it.