removing nicks/scratches from CDs

[Jonathan Clark]

Ib <ibeus at YAHOO.CO.UK> writes:

 > My Disc 1 has got a tiny, tiny mark on it that never used to throw my CD
 > player but now I'm finding that the track "EPCI" is skipping/jumping and
 > will no longer play properly. I've tried using Exact Audio Copy in an
 > attempt to get a copy of the track onto the PC so I can burn myself a
 > CDR so I can at least play the track in its entirety again but to no
 > avail, EAC won't read the data at that point.

If EAC won't read it then no other copy program will either.

I can suggest two options. One is just to try another PC with a different CD
drive (preferably a DVD or SACD drive) and see if that can read it.
Alternatively, invest in a CD cleaner/polisher kit, probably cost you GBP5-10.
This is the one I use:
http://www.amazon.co.uk/CLINIC-Cleaning-Restore-CD-RW-CD-ROM/dp/B0024GPRQA
It should have a little spray bottle of isopropyl alcohol, and a device to
hold a CD and whirl some polishing disks over it. You spray a little bit of
the alcohol onto the live side of the CD, polish it for 10 seconds, wait for
it to dry, and it should read just fine.

Turns out almost all nicks and scratches on a CD/DVD are in the layer of lacquer
which is on the surface of the disk, and do not penetrate down to the actual
pressing itself. The nick disrupts the laser beam enough that it can't get a good
reflection off the pressing. The alcohol dissolves a little bit of the lacquer and
allows the polishing disks to smooth out the surface again. Once it's nice and flat
(well, flatter), the laser can get a good signal off the pressing layer. Very
occasionally you might have to polish a CD twice.

Mary asked what EAC was. EAC (it stands for Exact Audio Copy) is a really useful
piece of freeware which lets you read CDs without errors. It uses a variety of
techniques. For example, it actually pays attention to any error codes which the
CD drive might send back when it hits a bad area, then it will try to re-read that
track a few times, if it still gets errors then it will read the area in "raw data"
mode "many" times (I think it's up to 64 times) and try and piece the real data
together from what it gets back. It also knows a lot about individual drives and
can compensate for some of the known weaknesses in some of these.

All in all, it's a must if you're doing any serious ripping. You can get it from
http://www.exactaudiocopy.de/

Jonathan