Have you ever tried to use an unbalanced CD in a high-speed reader? Do you cringe at the sound of vibrating sheet metal and scraping plastic as the unbalanced CD tears up your drive at 56x? Well fear no more:
The CD balancer works much like an automotive tire balancer; simply place the offending disk in the balancer and watch as it spins up and back down. The balancer finds the heavy spot and determines the proper corrective weight. Simply apply the appropriate supplied adhesive dot in the indicated location, and your CD is balanced and ready for use in your high-speed player.
(inspired by a recently purchased piece of software that was so badly unbalanced that it wouldn't read at all.)-- Freefall, Feb 04 2004 CD lathe for bevelng edges http://www.teac.co..../gads/gads_csi.htmlSorry. It is in Japanese, but this is the machine my friend and i used. CD Sound Improvement (balancer?) [countzero, Oct 04 2004, last modified Oct 21 2004] Guide to the unbalancing problem. http://www.mscience.com/faq17.htmlBad science award? Check paragraph two. [wagster, Feb 17 2005] OK, but only if the drive places the little adhesive dot, by its elf.-- Amos Kito, Feb 04 2004 i've never had any problems with that. fishbone.-- twelve, Feb 04 2004 Gee [twelve], I've never had cancer, but I don't oppose anti-cancer research (ok, so that's an extreme example). Most of my disks are fine too, this is for the few that aren't. I didn't intend this as something to be included as part of a drive, but rather as a separate device. Maybe it could be used by the stores (bring in your unbalanced disks for balancing) who would charge a small fee (50 cents?) per disk.-- Freefall, Feb 04 2004 I've had many a niosy CD ROM. The problem stemmed from excess room in the bay of my case, though. I can definitely see what you're talking about, so you get my bun.
//(inspired by a recently purchased piece of software that was so badly unbalanced that it wouldn't read at all.)//
You mean hardware?-- Letsbuildafort, Feb 04 2004 Maybe instead of putting on an adhesive dot on the disk maybe you could grind away a portion of the edge.-- KLRico, Feb 04 2004 [LBAF], It was an OfficeXP package. OK, so the "software" itself was fine, but the installation disk was severely unbalanced. I did manage to get the disk balanced (I borrowed a prop balancer from a friend who builds r/c planes), but it was a pain in the butt.
[KLRico] I had considered that, but I wanted a method that was non-destructive and reversible.-- Freefall, Feb 04 2004 This would work quite nicely in reverse. Surreptitiously apply a dotweight (or three) to your nephew's loathsome CDs containing the para-music of some cotton-mouthed rapster-gangster, and render them temporarily unplayable. At least until he twigs. +-- phlogiston, Feb 04 2004 I know nothing about CD ROM's but I bet you guys do. So you get my vote! +-- nomadic_wonderer, Feb 04 2004 I had one of those kinds of CD's lately. It was drivers for my Radeon graphics card. Its so badly balanced that nothing on it works, and accesing it takes several minutes. You can just hear it scraping away inside.
Dont see how it would be difficult at all. Have a little laser light that marks the location to put the dot. Just have to make sure the dot doesnt interfere inside the drive, or cause magnetic problems.-- excaliber, Feb 04 2004 nice, confined solution to an infrequent but real problem... c- bisket from me to you (balanced, natch.)-- DadManWalking, Feb 05 2004 Balanced CDs would, I assume, have better aerodynamic properties. You could carefully balance all your AOL CDs before seeing if they work as frisbees.-- hippo, Feb 06 2004 Why not create a drive mechanism that can adjust to counter the vibration of an unbalanced disk?-- TIB, Feb 06 2004 //Why not create a drive mechanism that can adjust to counter the vibration of an unbalanced disk?// - TIB
Because thats alot more expensive for CD drive makers, which means they wont do it (or it will be overpriced and expensive). Would grinding the edges be able to handle CD's that have really bad balance? Wouldnt that also start to hit the data sooner or later?-- excaliber, Feb 06 2004 I had one CD that sounded like it was tearing my drive apart and wouldn't read. I had to put it in an old, old 4x drive (one of those with the carrier that you put the CD into before putting it in the drive) to get it to read. Upon closer examination, the disk seems to be warped. How warped a disk can a typical CD ROM drive read?
A disk that's out of true could be a bit more of challenge to balance.-- half, Feb 06 2004 There was an article in 'Newscentist' about record companies planning on producing out of balance disks so that they couldn't be played in computer drives to prevent copying, seemed not only like a bad idea to me but almost criminal in knowingly selling a product unfit for purpose.
Have a bun :)-- scubadooper, Jul 20 2004 This exhists in the grinding form. Sorry, I have no idea what they are called, but i have personally used one. A friend who had way too much money and a bit of a fetish for music bought one. It supposedly ground the CD into perfect balance by beveling the edges. this was said to improve some high end clarity and response in the music. Im not quite proficient at discerning tones in music so i can not vouch for the effectiveness of the grinder, but it did balance the CD. Bun for you though, I would have never thought of such a device.-- countzero, Jul 20 2004 [countzero], I did search google for a while, and I couldn't find anything like it. Do you have a link available?[scubadooper] So am I going to have to re-install my circa-1994 2x drive in order to rip my new CDs?-- Freefall, Jul 20 2004 Really sorry, but i havent seen this person in years. At the time we were altering our states far too much for me to bother myself with such silly things as names, dates, scool, girlfriends etc... So no I dont have a link, but I will search myself at some point today.-- countzero, Jul 20 2004 Perhaps a drive could be made that is more tolerant of out of balance CDs?-- bristolz, Jul 20 2004 Not only is this idea fantastic, but I now know what that horrible noise is. Great! [Bristolz] - hasn't that been baked in laptop drives which 'hold' the cd in the centre? Siemens now ship these in their desktops.-- wagster, Jul 20 2004 Yes, perhaps. <looks at her laptop drive> Well, it does, sort of. Maybe 60% of the perimeter is enlosed.-- bristolz, Jul 20 2004 [Phlogiston], would that really work? What a mean and hilarious practical joke. If the stickers were transparent they might never catch on.-- spacemoggy, Aug 11 2004 [freefall] yes, sorry for the late answer :)-- scubadooper, Aug 11 2004 wouldnt simply having a slower cd drive lessen the problem? werent there myths about cds busting at high speeds?-- gnaeuspompeiusmagnus, Aug 12 2004 They aren't exactly myths. A "true" 50x CD drive is capable of exploding a damaged or unbalanced CD--this has been proven by expiriment on the television show "Mythbusters". Some drives available now claim to run 52x, but frankly, they are lying and actual speeds achieved are slower. An undamaged CD will retain structural integrity at 50x but does start to bend and oscillate alarmingly.
100x will destroy even a good CD--but in this case it may have just been the excessive acceleration when they kicked up the voltage to the motor, it's hard to tell. They had the CDs attached to a (woodworking) router, which has a lot more torque than a standard CD drive.-- 5th Earth, Aug 12 2004 What exactly does the speed (50x) refer to, RPM, Mach, the speed of a tortoise rolling down a 30% slope?-- brodie, Feb 17 2005 Video stores might also use this for DVDs, since they seem to like to put "property of" stickers on their disks in not-quite-balanced fashion, causing trouble in portable drives.-- supercat, Feb 17 2005 A standard CD player (1x) plays at constant linear velocity. The disk spins slower when an outside track is being read, and faster when an inside track is being read.
Many new high-speed drives are constant angular velocity. They spin at constant speed, no matter where they're reading from.The "50x" refers to the maximum data rate when reading from the fast-moving outer edge of the disk, when compared to the constant data rate available from a 1x drive. A 50x drive will usually average about 25x over the entire surface of the disk.-- Freefall, Feb 17 2005 But what is the speed of a 50x drive, 50 times what?-- brodie, Feb 17 2005 [brodie] I've found a site that appears to answer your question (link) but I'm a little concerned that they seem to be confused about the term rpm. If you read the second paragraph you will notice that they refer to a CD spinning at 580rpm at the inside while it's spinning at 230 rpm at the outside.-- wagster, Feb 17 2005 [wagster]: The phraseology is the problem, not the physics. Reread the sentence as: "This results in a 1X rotational speed of about 580 rpm [when reading data] near the inner diameter at lead-in. Rotational speed decreases as the pickup moves outward on the spiral track, reaching 230 rpm [when reading data] near the outer rim."
A 48x drive is one which can read data near the rim at 48x the speed such data would normally be read, i.e. spinning the disk at 11,040 rpm. Such drives have a top speed which is will below the 27,840 rpm that would be necessary to read data at 48x near the center using a single pickup.-- supercat, Feb 17 2005 Aha. So the rotational speed changes as the laser moves across the disc so that the angular speed under the beam remains the same. Thanks for explaining.-- wagster, Feb 18 2005 random, halfbakery