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Jordan_L
07-17-2009, 08:10 PM
Hi, I was able to get my cd out of the Clarion by taking it apart. I noticed there are three quite small marks on the readable side of the CD. I don't know if they are scratches or cracks, my guess are two scratches. The first two marks are coming from the edge of the CD, one is 1 millimeter long and the other is 2 millimeters long. The third mark is near the edge but not coming from and is still pretty small at 3/16 of an inch. I can't tell if these marks are cracks or just deep gashes. It appears the marks don't reach the top of the CD.

Let's say these three small marks were cracks, how would it damage the headunit if I were to play the cd? Is the only damage that could be done to the headunit caused by the disc breaking apart, or can the cd laser be damaged from skipping, ect.? As far as I know, most songs on the CD did not Skip.

ejschultz
07-18-2009, 01:07 PM
A scratched cd shouldn't damage the laser. Worst case is the motor for the laser will wear out prematurly from moving around due to the scratches. I would not recommend playing a cracked cd in any player. The crack itself will not damage the player, but the crack badly compromises the structural integrity of the disc. Most audio cd drives do not spin fast enough to make this an issue, however, it is not worth risking. If the cd explodes in the drive or player, the drive or player is garbage at that point. I'm speaking from personal experience as well as what I've heard from others.

Long story short:

scratches=okay
cracks=bad

Jordan_L
07-18-2009, 01:18 PM
Is there an easy way to see if the marks on the CD are scratches opposed to cracks?

How deep does a gash in a CD have to be in order to be considered a crack? I think I might have caused these marks when I attempted pulling the CD out with a pair of tweezers. The first two marks on the edge of the CD, when I tilt the CD, I can see the reflection of the marks on the silver part of the CD, so I'm guessing those marks are just on the top plastic layer.

If the song isn't skipping, is it safe to say that the laser reader is not having to move over the marks/cracks on the CD, therefore safe to use with the laser reader?

Like I said, the first two marks are about half the length of an Eyelash. The third is a bit longer.

ejschultz
07-18-2009, 01:27 PM
If it's a crack, you'd be able to feel it on both sides of the disc even if you can't see it on the label side. Like I said before, if it's a scratch, go ahead and play it. Don't worry about any damage to the player.

If you're really worried about the cd damaging the player, buy a new cd.

Jordan_L
07-18-2009, 03:22 PM
Deleted

Jordan_L
07-18-2009, 03:29 PM
The two really small gashes on the clear plastic ring around the CD can only be felt on the bottom, but not the top.

The third mark is definitely located on the top of the CD. When I tilt the CD in the light I can see a very faint outline of the scratch. When I lightly move my fingernail from left to right over the silver side of the CD, I can't feel it. I don't even think I can feel it on the top either.

The CD remains solid after bending it several times in the location of the marks.

The only two marks that concern me are the ones on the bottom of the CD that are on the clear plastic edge and extend over the silver part a little. Can deep scratches cause damage to the laser mechanism by moving to much around the two deep scratches, or does that only apply to cracks?

ejschultz
07-18-2009, 04:01 PM
Immediate damage can only be caused by a cracked disc breaking in the drive. A scratch will only cause the motor that moves the laser to wear out more quickly. It will still take years of this abuse like this before the laser wears out, so long as it's not a super cheap cd player.

The damage you're describing appears to be nothing more than just a few scratches. If the song on the disc don't skip, the scratches aren't even affecting playback and there's nothing to worry about.

Jordan_L
07-18-2009, 05:17 PM
Oh ok, so if the song does not skip (which most don't) that means the laser is not having to avoid scratches and it is operating normally?

ejschultz
07-18-2009, 05:30 PM
Oh ok, so if the song does not skip (which most don't) that means the laser is not having to avoid scratches and it is operating normally?

Yes.

Jordan_L
07-18-2009, 06:08 PM
Thanks for your replies :thumbupw:

ejschultz
07-18-2009, 06:10 PM
No problem.

Jordan_L
07-18-2009, 07:32 PM
One last question :), I noticed that I scratched off a little bit of the top label on the retail CD from trying to feel the scratch, could this cause issues in the headunit while the CD is spinning?

ejschultz
07-18-2009, 07:38 PM
One last question :), I noticed that I scratched off a little bit of the top label on the retail CD from trying to feel the scratch, could this cause issues in the headunit while the CD is spinning?

No.