DIY CD "scratch doctor"

[jives11]

Hi,

I have bought a few CD's second hand for a few pennies. They are badly scratched, mostly play but skip in a few places.

I have seen a number of abrasive CD repair systems, I wonder what peoples experience of such devices is and if there are any 'home grown' alternatives.

All my Cd's are kept clean , but it would be fun to see if these discarded ones could be repaired

[Christer]

First try improving the CDs themselves. Rubbing with toothpaste and some water has improved scratchy CDs considerably for me.

[planetbass]

Hi - first post on this site. I just bought a very rare CD that the vendor told me "played perfectly" but my Yamaha DVD player, Aiwa XC-700 CD player and Marantaz DR700 CD recorder skip like mad when they play it - the Yamaha less than the others though...

I moaned to the vendor who gave me part of my money back, so now I've ordered Wipe Out Ultra which is supposed to let you polish out quite bad scratches. Unlike the earlier Wipe Out (and toothpaste) it's not supposed to leave a white haze on the disc.

I ordered this today so I'll try it and report back to you.

[EchoWars]

I use Meguiars plastic polish.
This:

Followed by this:


I used to use automotive rubbing compound (the white light-duty stuff) followed by regular auto wax. Works well, but the Meguiars works better.

[jives11]

Originally posted by planetbass
Hi - first post on this site. I just bought a very rare CD that the vendor told me "played perfectly" but my Yamaha DVD player, Aiwa XC-700 CD player and Marantaz DR700 CD recorder skip like mad when they play it - the Yamaha less than the others though...

I moaned to the vendor who gave me part of my money back, so now I've ordered Wipe Out Ultra which is supposed to let you polish out quite bad scratches. Unlike the earlier Wipe Out (and toothpaste) it's not supposed to leave a white haze on the disc.

I ordered this today so I'll try it and report back to you.

Thanks I'm interested to hear how you get on. Oddly the CD player I have which is the least fussy about condition is an old Philips CD104. It will play almost anything including CD-R's that my newer player or DVD will not touch. They don't make em like that anymore

[quickshift]

Mur car polish is very good becase it's very slightly abrasive.

I have used it on CDs and bike helmet visors with great results it actually polishes the scratches out, the visors are cleaned regularly and the scratches never reappear so it isn't the coating it leaves that does the trick.

It also keeps dust of TV and pooter screens for ages longer than using just a normal cleaner.

Works pretty well on cars and bikes too

[jives11]

Thanks to one & all for the suggestions.


I tried the toothpaste trick & it works (mostly). In a cupboard I had a free sample of "Arm & Hammer" brand toothpaste. This has bicarbonate of soda in it, so I guess may be a slighly more abrasive toothpaste than the usual stuff.


It certainly got rid of much of the jumps later in the disk, though alas I still have a persistent skip in the middle of the Bruch Violin Concerto Adagio. A bad place

Q: I know CD's are read from the middle out. Is there a method to figure out how many minutes into a disk relates to a specific radius. Even approx. it would be useful to know that 10 mins in relates to approx 1cm from the edge of the center hole, or am I oversimplifying ? It's just it would be nice to know where to concentrate my polishing

[Christer]

Originally posted by jives11


I tried the toothpaste trick & it works (mostly). In a cupboard I had a free sample of "Arm & Hammer" brand toothpaste. This has bicarbonate of soda in it, so I guess may be a slighly more abrasive toothpaste than the usual stuff.

I'm glad to hear it worked for you too. Actually I don't think it's the chemicals in the toothpaste that matters, but what they put in it to get a mild sanding effect (not sure what to properly call it in english).

I also had a CD with very bad scratches that I bought on Portobello Road 15 years ago. In particular it had one scratch in the second movement of Schuberts 9th that made my CD player would´t get past. It got trapped in a five second loop that just repeated indefinitely. The toothpaste was never sufficient to make this scratch unnoticeable, but at least the CD became playable past this point. I used a particularly gentle tootpast, but I guess a standard one might work better.

[Ron E]

Originally posted by Christer
Actually I don't think it's the chemicals in the toothpaste that matters, but what they put in it to get a mild sanding effect (not sure what to properly call it in english).

That would be "abrasive".

One of my other hobbies is amateur telescope making. I have some mirror grinding abrasives. Cerium Oxide polishing compound made into a paste and rubbed in with a finger works quite well for removing fine scratches. using 10 micron first will get out many deeper scratches, and using a progression of abrasives is required for the really deep ones.

One thing that might make an unplayable disc playable is to try Pledge spray on furniture wax. When I was young my aunt used to use this on her glasses to cover up scratches. I thought she was crazy, but it really works - only until you wash them, though. I wouldn't recommend this as a long term solution, because CD plastic is quite vulnerable to chemical attack, but it might work temporarily or long enough to rip a copy of the CD.

[quickshift]

Originally posted by jives11


Q: I know CD's are read from the middle out. Is there a method to figure out how many minutes into a disk relates to a specific radius. Even approx. it would be useful to know that 10 mins in relates to approx 1cm from the edge of the center hole, or am I oversimplifying ? It's just it would be nice to know where to concentrate my polishing

You should be able to see the gaps between the tracks on the surface of the CD.

10 mins in from the start is about 5mm in from the center.

It's not that easy to work out mathematically and virtually impossible to measure accurately as such... I looked on a CD with a 10 min song as the first track.

Useless info about CDs

The speed of the CD varies from 200 to 500 RPM

The track width is 0.8 um and the gap between tracks is 1.6 um.

The total track length for a CD is over 60,000 meters.

1 minute of audio is about 822 meters of physical track.

When CDRs first came out, for each CD that reached the required standard, 15 were thrown away because of manufacturing defects.