How to fix a scratched DVD or CD | Tech Blog
We’ve all been there. You lend a buddy a copy of your favorite DVD and it comes back looking like they used it to rip the shingles off of their roof. Sure, you could go out and buy another copy, but that will cost you precious Amazon dollars or a lengthy excursion to Best Buy. Luckily, there are a few methods to fix a scratched DVD or CD that you should give a shot before you disown the irresponsible guy you once called a friend.
Before we continue, it should be noted that the best way to deal with a scratched disc is, in fact, to simply replace it either through the store where you bought it or by getting in touch with the manufacturer. Many video game publishers will send you a new copy of their title in exchange for the damaged copy and a nominal fee, for example. You should also keep in mind that all of the methods below have the very distinct possibility of further damaging your discs, even when done carefully using our guidelines.
It’s important to note that these methods will not work with Blu-ray discs, given those discs use a harder coating that’s more difficult to scratch and damage. The downside to this is that once it does scratch, the Blu-ray disc typically becomes unusable and has to be replaced. Minor damage may be corrected with a micro-fiber cloth, but the data density and layers prevent any of the options outlined below from working particularly well or even being advisable. Error-correction features on the best Blu-ray players may help them to ignore scratches, of course.
It’s also a good idea to back up your DVDs, CDs, and Blu-rays by copying the data to a hard drive, also known as “ripping.” This will keep your music and movies safe and watchable for as long as you need — provided your hard drive doesn’t become damaged — and if you still want physical copies, you can simply burn them onto a rewritable disc.
There are all sorts of ways you can damage a disc, but it’s important to identify how deep a scratch is or what caused the disc to malfunction before proceeding. The first trick is to identify that the problem is actually the disc, usually done by trying to play it in another device with a disc drive or inserting another disc into the original drive that gave you issues.
What you should know before you begin
How do scratches affect discs?
A CD or DVD is composed of layers. At the top is a layer of plastic, with the label printed on the surface. Data is stored on the disc in the form of ones and zeroes. When a disc is printed, a laser burns tiny pits into the plastic, so that the surface consists of various pits and flat surfaces called “lands.” Beneath this is a layer of reflective aluminum, and it’s important: When a CD or DVD players reads the disc, it runs a laser along it. The laser detects whether it is running over a pit or a land before the aluminum reflects the laser back to the player.
Finally, the bottom layer of the disc is a layer of polycarbonate, which is meant to protect the data from damage. If this protective layer becomes scratched, the laser’s path can be altered, thus hindering its ability to accurately read the pits and lands. In order to fix the disc, one must either buff out the scratch or fill it with a transparent substance, so that the laser can travel through to the data.
Five tips before you start
Although we cover different methods for cleaning and resurfacing your discs, it’s important to remember a few key rules if you want to save yourself a headache while going through the process.
Step 1: Wash and dry your hands before handling your discs. It’s surprisingly easy to mess with the delicate data imprinted onto a disc’s polycarbonate layer, and both grease and oil are known to cause playback issues even if the disc shows no signs of physical damage. Better still, put on a pair of latex gloves, if you happen to keep them around.
Step 2: The best way to clean your discs, with any material, is to start at the center of the disc and work your way outward in a straight line. This allows for a better grip while cleaning and lets you avoid damaging any of the data printed onto the polycarbonate layer below. The reason for this is that the data runs in a spiral around the disc, as on a vinyl record. Because the disc spins so fast, the reader has to be able to compensate for missing bits of the data as it goes, and when a scratch runs straight out from the center of the disc to the edge, it’s a lot easier for the algorithm to catch the error and fix it automatically.
Step 3: Tray-loading drives may be more likely to read a damaged or scratched disc than slot-loading drives. If possible, it’s a good idea to use one of these drives when trying to salvage a disc to lower the number of variables at play.
Step 4: Given that the layer of data that’s encoded onto the polycarbonate surface is so close to the top layer of the disc, scratches and dents on the label can cause read errors in the same way a ding in the reflective surface can. Make sure to store all your discs in cases or on spools, and handle them by the inner ring to avoid damaging the data.
Step 5: The best way to repair discs is not to scratch them in the first place. It sounds silly, but using good cases and spools can significantly reduce the chance of damaging a game or DVD, which will, in turn, save you the hassle of repairs in the first place.