Re: (idm) CD scratch removal - thanks IDM

From FreyGuy
Sent Tue, Jun 23rd 1998, 23:59

FYI, here's what I did, exactly:

I had 2 discs that were bad, but the worst scratched one wouldn't play
the last 4 tracks without either skipping into a loop or simply skipping
back and forth at several second intervals (the other only had 1 track
damaged).  The scratches were evident and quite deep (I was afraid that
they had been deep enough to damage the data layer).

Caution: Only do this if you have problems playing the disc... do not
attempt if they are simply cosmetic because tooth paste *can* worsen the
situation in that case.

1.  Place the CD, data side up, on a flat surface for stability.  I
placed a small dab of Colgate Platinum "Mildmint" whitening fluoride
toothpaste (no, I don't own Colgate stock :-) directly on the scratches
(I have, for some reason, 3 different kinds of toothpaste in the
house?).  It is an opaque-white toothpaste.  Use non-baking soda
toothpaste (baking soda is too abrasive for our purposes)...the gel
might not be abrasive enough.  I'm no toothpaste expert though... I'm
just telling you what I tried... Gel might work with more repetition. (I
believe there exists a fine balance).

2.  I used a small bit of paper towel, and covered my index finger with
it for precision; no extra pieces making the toothpaste spread too
much.  The key is to use something soft for your buffing cloth, like a
smooth cotton tshirt for example (in fact, I believe the cotton T would
be gentler than a paper towel.. but its what I had handy).
Gently, using your fingertip, "buff" the surface of the scratches while
trying to keep the toothpaste on only the affected area of the disc.
This is to minimize the problems that you would cause to the
non-affected areas.  Do this softly but persistently, patience may be
required.

3.  Then, I washed it under luke-warm water to get the paste off.
Examined the disc closely to see how the scratches were coming along.

4.  I decided that they needed another go, so I repeated steps 1,2,3.

5.  The scratches are still quite visible, but I could tell a noticeable
difference in their "appearance."  They just "looked" not-as-deep as
before.  Also, note that you will see a slight "dulling" of the surface
of the CD where you were buffing due to the nature of the toothpaste's
abrasives (this is why the term "gently" is necessary)... you could
easily dull the clear coating enough to skew the laser so that it
wouldn't play that area at all.  However, a little dull won't hurt
anything, I've seen some pretty sad looking CDs play (as I'm sure we all
have).

So, after rinsing it clean and drying it thoroughly for the last time, I
tried it out in the deck... and the previously unlistenable songs played
without one skip.

I was quite surprised, to be honest.  You're results may vary, but
Irene, you may want to give it another try, maybe with a white
toothpaste (remember, non-baking soda).   I believe that its necessary
to take your time and to keep much attention to detail during the
process... if its overdone, it can worsen the situation; which, in my
case, it couldn't get worse.. the songs wouldn't play, which is why I
decided to attempt this in the first place... last resort.  If its
underdone, it will have no effect... but its better to "under-do" it and
do repeated trials, that to ruin it altogether on the first try.

While doing the buffing, keep in mind how the disc is constructed.
Simply stated, its a piece of plastic coated with a metallic, reflective
surface, then encoded with the musical signal.  Then a protective clear
coating is put on top of that.  This coating must remain clear enough
for the laser to pass through, within error-correcting limits.  Plus,
you shouldn't buff so hard/deep that you get into the data layer of the
disc, which will definitely ruin the whole show.
The goal is to buff enough of the clear layer off around the scratched
area so to eliminate the effects of the scratch (laser skewing) without
making the clearcoat opaque. The idea is to "smooth out" the scratches

This method will not fix all scratches due to the severity of some
scratching (sometimes the scratch gets into the data layer, but it
worked for me twice now, who knows what my luck will be in the future.

Patience and Good luck =;-)
!Kev!
=-=-=-=-=-
FreyGuy         <Everyday is Freyday>
Network/Notes Administrator
NMB Technologies
ICQ:4784088
"Like the generation of the revolutionary dead,
 we have a destiny to create." -Alvin Toffler

=-=-=-=-=-=-=-=-=-=-
Irene McC wrote:

> On 23 Jun 98, jif wrote re: Re: (idm) CD scratch removal - than:
>
> >  do you have to use gel, or is paste just as good?
>
> Nyeeaaagh, the gel didn't work.  Maybe I ought to have used white
> paste?
>
> At least the bits that played before *still* play, so it's no worse
> than I started out with - but it's surely absolutely unimproved...