While searching for something to polish up my brass paintball gun, I stumbled across the perfect compund to repair CD's.
Step 1: What You Need!
1 CD that is in desperate need of repair
1 roll of paper towel, and not necessarily the soft stuff
1 roll of reasonable soft and durable toilet paper
1 cloth do place the CD on as to not damage it, and soak up excess Brasso
1 Can of Brasso Metal Polish (MUST BE BRASSO)
Take a look at the intro picture to see what I used.
Brasso is a very unique polishing agent. It is just abrasive enough to remove mild to moderate scratches without being so abrasive that it will scuff the polycarbonate plastic..
One of it's listed uses on the back of the can is for polishing plastic watch crystals.
Step 2: Polishing Part 1
Neatly fold some paper towel up and apply a moderate amount of Brasso. The stuff is runny and has a very strong order so try to not make a mess.
Hold your CD securely and rub the CD with the Brasso covered paper towel in circular motion similar to the way you would wax a car.
You can apply a decent amount of pressure to work out deep scratches but don't crack the CD. The less pressure you use the better the final surface, but you can also go through stages of polishing. Work out the deep scratches then go over with a finishing, light pressure, polish.
I've also used a Dremel and/or a substancial amount of hand polishing to buff out realy deep scratches, but you have to be sure to taper the plastic out gradualy otherwise it will create a reading problem when the laser is directed off at an angle.
Step 3: Polishing Part 2
Periodicaly stop polishing with the paper towel, allow the Brasso to haze, then use the toilet paper to rub off the haze.
This step actualy does a decent amout of polishing in it's self so i recomend doing it often.
Basicly when you feel that the initial Brasso aplication is running thin or the section of paper towel is wearing out, stop, dry polish with T.P., then start over.
Step 4: The Finished Product
I usualy use a rougher abrasive on target areas then use the brasso to correct those scratches. It's safer than a dremel, and still effective.
When you are done you should have a surface that is readable, with only light insignificant swirl marks.
You may want to try using toothpaste at this time to finish it to a like new surface.
Happy polishing, and be sure to be in a ventalated area.