Cleaning CDs

I've never had any trouble using Windex and a soft cloth. Ideally, you should clean from the center out, or edge in, not in a circular motion. That way, any scratches you make will not run parallel to the tracks. I wouldn't use alcohol because it might damage the label. Alcohol will also dissolve the dye layer of a CD-R if there are any scratches in the protective layer. Andy Cuffe

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I use a small drop of liquid dishwashing detergent and some water. Spread this around gently with a clean finger. Let work there and slowly add more water. Rinse gently under running clean water.

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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I use warm water and dishsoap, working only from the center directly out to the edge with a *clean* finger. Dry with something lint free, probably the ideal thing for drying would be the cloths they sell for eyeglasses.

John

The main point is, other than clean materials, how you clean the CDs. Radially not circumferentially. Try this to demonstrate. Find a junk but fully playable audio CD. With a steel nail scratch a radial line and the CD will probably play the same. Now on another part of the CD scratch a similar line 'tangentially' and I doubt the CD will play the track/s that is at the centre of that scratch

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

Not quite cleaning, but dealing with scratches ...

If you have a scratched or scuffed disc, try metal polish of the ' wadding ' type. Rub vigourously around the scratched area ( there's no need in this case to worry about doing it radially rather than in circular motions, but that said, I agree with what everyone else has commented about not CLEANING with tangential movements ). You only need to work the wadding around the scuff / scratch for 30 seconds or so, then let the polish residue dry to a white haze for another 30 seconds or so. Now polish off with a lint free cloth, and you will be amazed that the damage has apparently completely disappeared.

I don't think that it does actually go, rather that the metal polish leaves behind an oily protection layer, which ' fills ' the scratch or scuff in, and has a refractive index very similar to that of the plastic. Never-the-less, the effect is to completely recover a disc with poor playability due to damage, in all but the most severe cases. Also works for computer CD ROMs that the machine has dificulty with for the same reason.

Arfa

CLEANING

leaves

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Anyone tried one of those CD surface heating and rotating gizmos ?

Hello all,

First, I agree with most of the posting here, no circular motions, gentle cleaner, lint free cloth.

If the disc is really important, find a better local video rental place that has a real disc resurfacing machine. The one in my area has a unit that uses up to 5 grit levels in a wetted condition and does amazing things with damaged discs. It will even remove the swirl mark left by the home units that cause as many problems as they solve. The reason I don't suggest that you buy one of these professional machines is that they cost around $2500. They charge $3 per disc.

The system is also sold with a specialized PC 'disc analyzer' that scans the disc, and tells how many bad or damaged sectors there are, and where they are on the disc. The analyzer is around an additional $1500, so I wouldn't suggest buying one of those either.

Regards, Tim Schwartz Bristol Electronics

Richy wrote:

What about these things, gimmick or not , I thought they heated the surface but probably not ? eg

-.asp

kaboomie

It does not matter what direction you wipe the disk . I dont care what someone said or the myths that go with it . There is no such thing as a ``lint free`` cloth or lint free anything . Just use some sort of soap , Windex is always handy .

We have one of those pro cd cleaning machines at work it sits right behind my workbench . It has a water tank on top that sprays a constant stream of water on everything . You can start with different grit wheels depending on how bad the disk is . Normal every day scratched disks will come out like new with only the last step which is a foam pad with goop on it . This machne really does a good job . I have fixed some totaly un-playable disks in it .

Where do you get the idea that the direction of wipe is a myth ? The data layer on a CD or DVD is a spiral behind a plastic guard layer. If you put a scratch radially across a vinyl record, it will click every time the stylus passes over it. If you put a scratch along the groove, it will disturb the output for as far around the groove as the scratch goes.

Likewise, if you put a scratch across the protective layer a CD or DVD, it will be largely ignored because of the way the data is encoded by interleaving and spreading it around. However, there is a limit to the amount of data you can corrupt before the hardware and software error correction systems fall over, and you lose output which is correctly usable by the servo and music / video data DSPs. This becomes even more important on DVDs which have much less margin for error because of the much smaller data pits, and the speed at which the data is read off the disc, and on any player where the laser is even slightly below spec.

Whilst it may be true that your fancy machine spins the disc and applies several grades of sandpaper or whatever, it is a professional machine, and does this in a controlled and designed manner. This is why it gets away with circular cleaning. Joe User, on the other hand, is a ham fisted biological machine, who can't tell the difference between carefully cleaning fingerprints off a disc, and doing the disc more damage by scrubbing around it with a caked snotrag. I therefore stand by the contention that the best way for an inexperienced average user to clean a disc is by rubbing gently across it, with the aid of a little dishwashing liquid to help remove greasy marks.

As far as there being no such thing as lint free cloth, there are many manufacturers who would disagree with you, and advertise products as exactly that. Whilst no cloth can be declared perfectly lint free, synthetics such as polypropylene are considered to be near enough to meet the definition. Next time you clean your glasses, try using a cotton dish drying towel instead of the polyprop cloth that came with them, then tell us again that that a lint free cloth doesn't exist.

Arfa

Terrific post!

Wish all of mine were this good. ;-)

Mark Z.

I tested this once with an old CD. I put a very deep scratch across the diameter of the disc with a razor blade. The CD still played perfectly although it took longer to seek to a track. We all know that even a light scratch in the wrong place will render a disc unplayable.

Andy Cuffe

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