Exploding CD-R disks! Myth or reality?

sharkeeper

Lifer
Jan 13, 2001
10,886
2
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I see this topic surface every once and a while and while reading some articles over at CDRinfo, I've noticed that some drives have safeguards that must be overriden to achieve advertised speeds. Plextor even claims that its fastest burner is "reinforced" to contain the remnants of an exploding disk if such an event should occur. As an end user in a typical "safe" computer environment, that sounds kind of scary to me.

I understand that Sony's (48x) drive burns at 40x tops, however if you hold the EJECT button down after inserting a blank, this limit is overridden and 48x recording is possible. Furthermore, they are releasing a 52x drive and the firmware for that drive is floating on the net and it is possible to flash the 48x model to burn at 52x with no user intervention! I wonder what the risks are? Sounds like it would be fun to do perform some non destructive as well as destructive tests on these. Too bad I won't have the time. :|

-DAK-
 

chizow

Diamond Member
Jun 26, 2001
9,537
2
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Apparently this Spinal Tap-esque phenomena of "spontaneous combustion" (figurative, not literal for all the wannabee post police) was quite common with those Kenwood 72X CD-ROM drives. Maybe you could probably pick one up on Ebay and see if you can catch it on tape. :D

Chiz
 

sharkeeper

Lifer
Jan 13, 2001
10,886
2
0
I actually HAVE a true-X 72x (ZEN) and it spins much slower than a 50+ reader because it uses seven beams.

The drive works fine, but is a horrible ripper (DAE) and has a nasty habit of locking the machine bad when a scratched disk is inserted. So it has basically been collecting dust since August of 2000. I have another in NON WORKING condition courtesy of my fist, but that's another story. :eek:

-DAK-
 

Mark R

Diamond Member
Oct 9, 1999
8,513
16
81
This phenomenon is certainly real, and is the reason why CD-ROM drives have no progressed past "52x". That (11,000 rpm) is the highest speed that can be safely tolerated by the discs. (There is a fair bit of safety margin here, but I believe that some researchers found that at 20,000 rpm, every CD they tried disintegrated)

At that speed they are already subject to acceleration of over 8000 G, and if spun faster can distort and stretch significantly (over 1 mm is possible). A damaged (cracked) or poorly manufactured disc can shatter at that speed with serious consequences. A disc could disintegrate into hundreds of pieces of razor sharp shrapnel travelling at over 150 mph. There have been reports that some batches of cheap CD-R discs failed relatively frequently in 48 or 52x drives.

DVD discs are significantly stronger mechanically, with an estimated maximum safe speed of nearly 20,000 rpm - presumably to remain compatible with future DVD-ROM drives which could potentially reach 40x. However, the consequences of a disc disintegrating at that speed, would be considerably more serious than at current drive speeds. I would expect steel reinforcement to be mandatory for such drives.
 

Amorphus

Diamond Member
Mar 31, 2003
5,561
1
0
steel? that would be overkill, methinks. some cheap fiberglass/carbon fiber ribbing will do fine. but CDs will be thicker, too. I'd expect ones 1.5x the size of our current ones.

what does FUBAR stand for?
 

0roo0roo

No Lifer
Sep 21, 2002
64,795
84
91
yup cd's are cheap vinyl from what i remember, cd case material i think. dvds are polycarbonate, much stronger. more costly
 

RalfHutter

Diamond Member
Dec 29, 2000
3,202
0
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Originally posted by: Amorphus
steel? that would be overkill, methinks. some cheap fiberglass/carbon fiber ribbing will do fine. but CDs will be thicker, too. I'd expect ones 1.5x the size of our current ones.

what does FUBAR stand for?


AcronymFinder.com, an invaluable tool for the internet.
 

MadRat

Lifer
Oct 14, 1999
11,960
278
126
Originally posted by: Mark R
This phenomenon is certainly real, and is the reason why CD-ROM drives have no progressed past "52x". That (11,000 rpm) is the highest speed that can be safely tolerated by the discs. (There is a fair bit of safety margin here, but I believe that some researchers found that at 20,000 rpm, every CD they tried disintegrated)

So I should remove this 56X? How else can I feed a 52X burner...

 

0roo0roo

No Lifer
Sep 21, 2002
64,795
84
91
its true, some discs shatter easier i bet. i've bent many discs in half in my day(bad burns/aol cds etc). some break and shatter, others bend quite a lot!
 

sharkeeper

Lifer
Jan 13, 2001
10,886
2
0
So I should remove this 56X? How else can I feed a 52X burner...

Buffer to HDD first or do it on the fly. Burn Proof is your friend! I burn at 48X on the fly using a Toshiba DVD reader (40X read) and it only hits burn proof if the source disk is dirty. Remember most CD-R's are P-CAV or CAV so the starting speed is 20~24X tops and goes to 48X~52X end. (Of course that is true with the readers as well!)

-DAK-
 

pm

Elite Member Mobile Devices
Jan 25, 2000
7,419
22
81
If you unbalance a CD - by, for example, putting a sticker on one side of the disk near the outer rim - I've heard you can induce the disk to shatter. Although I have also heard that the newer drives have detection systems that can detect the problem.

Things falling apart at 11000 rpm are pretty scary. I had a 9 inch plastic propeller fly off of one of my model airplanes due to a slightly loose hex nut. It flew past my face and slammed into the ceiling where it sank 3/4" deep into the wallboard and stuck there in the ceiling until I got a chair to pull it down. It was rotating at about 6000 rpm.
 

Jeff7

Lifer
Jan 4, 2001
41,596
19
81
Originally posted by: pm
If you unbalance a CD - by, for example, putting a sticker on one side of the disk near the outer rim - I've heard you can induce the disk to shatter. Although I have also heard that the newer drives have detection systems that can detect the problem.

Things falling apart at 11000 rpm are pretty scary. I had a 9 inch plastic propeller fly off of one of my model airplanes due to a slightly loose hex nut. It flew past my face and slammed into the ceiling where it sank 3/4" deep into the wallboard and stuck there in the ceiling until I got a chair to pull it down. It was rotating at about 6000 rpm.

Yeah, like it starts wobbling, and when it begins to resonate, the force of that shatters it.
My Giants: Citizen Kabuto (think it was disc 1) exploded in a Pioneer 16x/40x DVD drive. It was the usual description - the disc spun up, followed by a really loud WHAP from the drive. The insides of the drive only lost a few small pieces of plastic, which don't seem to really do much anyway - it still worked too. I wonder what would happen to anyone sitting in front of a slot-loading CD drive when a disc shatters? Those pieces are quite sharp, and they have a lot of force in them.
Oh, there's supposed to be a 54x Plextor drive coming out soon; I think I saw the link posted in this forum. I hope that thing has an armored faceplate.
 

TKHDebater

Senior member
Jan 2, 2003
241
0
76
crap, so i shouldnt be burning my 32x CDs at 52x? I overheated my old liteon by burning 27cds in a row.... It'd be painful to have another die on me...
 

AndrewNF

Senior member
Sep 1, 2001
284
0
0
Originally posted by: Mark R
This phenomenon is certainly real, and is the reason why CD-ROM drives have no progressed past "52x". That (11,000 rpm) is the highest speed that can be safely tolerated by the discs. (There is a fair bit of safety margin here, but I believe that some researchers found that at 20,000 rpm, every CD they tried disintegrated)

At that speed they are already subject to acceleration of over 8000 G, and if spun faster can distort and stretch significantly (over 1 mm is possible). A damaged (cracked) or poorly manufactured disc can shatter at that speed with serious consequences. A disc could disintegrate into hundreds of pieces of razor sharp shrapnel travelling at over 150 mph. There have been reports that some batches of cheap CD-R discs failed relatively frequently in 48 or 52x drives.

DVD discs are significantly stronger mechanically, with an estimated maximum safe speed of nearly 20,000 rpm - presumably to remain compatible with future DVD-ROM drives which could potentially reach 40x. However, the consequences of a disc disintegrating at that speed, would be considerably more serious than at current drive speeds. I would expect steel reinforcement to be mandatory for such drives.

AOpen actually makes a 56x model, sold here. Link
A Google search for 60x came up with this drive, although I don't see any way to buy it. Damn, I wanted to blow some discs up! Link
 

zephyrprime

Diamond Member
Feb 18, 2001
7,512
2
81
steel? that would be overkill, methinks. some cheap fiberglass/carbon fiber ribbing will do fine
Those materials are more expensive than steel. Steel is cheap.