Will Cds explode at high RPMs? Mythbusters find out.

[Skiguy411]

Its on now on the discovery channel. Find out now!

 

[aphex]

My Yamaha 44x F1 CDRW drive has shattered 2-3 of my cd's while i was ripping them into mp3's

 

[Amorphus]

I have a video of a guy playing with a CD on a dremel.

its quite cool, but I couldn't find it again if I tried.

 

[Cooljt1]

yeah, awhile back there was a site witha guy putting cds on a dremel and spinning them at 30k rpm. they shattered and also went creazy, it went up the door and hit the wall like 3 times. anyone know the site with that

 

[Cooljt1]

cds shattering with a dremel

 

[ReiAyanami]

yes, because EA had constant problems with their low quality CD's exploding in people drives

 

[MikeMike]

well they got them to explode, but it was, slow down speed up movements that did it from the cd drive. and they used an electric grinder.

(spoiler alert, oops sorry, to late)

they tried to find a ducks echo, and discovered even highly advanced equipment could hardly find it, but it was there.

nother good one, is where they see if a person can survive being in an airplanes wheel well for a whole flight.

MIKE

 

[Ulfwald]

That is some serious SH!T. Those cds were really moving.

 

[pennylane]

I broke a CD ripping it once...

 

[BeauJangles]

Mythbusters is awsome

 

[FrustratedUser]

Originally posted by: BlinderBomber
Mythbusters is awsome

Funny show.

 

[tcsenter]

Isn't the point to find out if CDs will shatter at realistic RPMs? You know, like the RPMs of those devices in which people report their CDs shattering?

I am fairly confident anything will come apart if you spin it fast enough.

 

[TheBoyBlunder]

I remember that one...that was hilarious. The best part of the show is after they prove or disprove the myth, they usually try to duplicate the results if it involves blowing stuff up.

 

[CQuinn]

Originally posted by: tcsenter
Isn't the point to find out if CDs will shatter at realistic RPMs? You know, like the RPMs of those devices in which people report their CDs shattering?

Yes, and that is what they were testing against; or to be more precise, they were trying to
determine if the CD-shattering story was real or an Urban Myth.

I am fairly confident anything will come apart if you spin it fast enough.

Yeah, but after you prove or disprove an urban myth, then you have an excuse to blow
stuff up

That's part of the appeal of the show, not just testing myths, but figuring out the
most funny and outrageous way possible.

 

[tcsenter]

Yes, and that is what they were testing against; or to be more precise, they were trying to
determine if the CD-shattering story was real or an Urban Myth.

But their test couldn't prove or disprove the 'rumors'. Nobody was complaining about their CDs shattering at the end of a Dremel @ 30,000RPM. Their "myth busting" is a bit like this:

"It has been rumored that tossing a coin from a sky-scraper will develop enough velocity to kill people on the street below and penetrate automobiles. We are about to find out if tossing an object from a sky-scraper could be deadly, by rolling this 16 lb Columbia bowling ball over the edge of a 65-story building to see what she can do."

Just as one would reasonably ask 'how did a coin get to be a bowling ball?', one might reasonably ask 'how did the rotational speeds of a 52x CD-ROM get to be 30,000RPM'?

CDs with an unseen defect might come apart at CD-ROM RPMs while those free of defects would require exponentially higher RPMs to produce structural failure, which neither of the tests can prove or disprove without testing thousands of CDs at CD-ROM RPMs to root-out the ones with defects.

Just an indication of how people who don't know what the hell they are doing can really screw up a purported "test" and produce 100% meaningless results.

On edit: Its entirely ok to do this kind of thing for pure entertainment value, as long as they disclose something like "These tests have absolutely no basis in reality and the results of our tests are completely meaningless. We are conducting this test purely for entertainment reasons, and although we might like to fantasize about being real scientists, we're no more qualified to call ourselves scientists than the average high school graduate."

 

[geno]

tcsenter, I wouldn't say it's completely useless, they found out what kind of RPMs it takes to shatter your average CD-R... they claimed a 56X/52X drive can get up to 30k RPMs, I really don't know the actualy numbers. So I don't see how it's irrelevant if in fact consumer CDROMs spin that fast. The other half of the myth was the fact that people were getting hurt by this phenomenon, the myth claimed that shards of CD came exploding out of the case, which is something else they disproved once they found out that the shards wouldn't even penetrate the metal casing of a CDROM.

 

[MooseKnuckle]

Cool...

 

[StageLeft]

tcsenter

is right that some of their tests are fairly silly and not worth much besides entertainment. I'd be just as happy watching them blow things up all show personally.

 

[DannyBoy]

Originally posted by: Skoorb

tcsenter

is right that some of their tests are fairly silly and not worth much besides entertainment. I'd be just as happy watching them blow things up all show personally.

:beer:

That was funny seeing that cd run across the room 3 times!

 

[brxndxn]

My brother's former Kodak (liteon I think) 52x CDR broke his Baldur's Gate 2 cd.. He played the game for years before the drive broke it. We were all in the room and about 5 minutes after inserting the cd into his newly-installed drive, we heard what sounded to be like a gunshot right outside the window. We all ran outside to see what it was.. nothing. We looked all over my bro's room.. nothing. Finally, my bro ejected his cd drive to find 100's of shards of a cdrom.

so, it is not an urban legend... at least for me.. cause' it happened with a normal cd drive.

 

[Azraele]

It happened to me. A friend leant me a game to play (one of the sims), and it broke in the drive. Whoops.

 

[DannyBoy]

Ive never had a cd break in the drive, i have however had my cd rom drive open when the cd was spinning EXTREMELY fast, thing flew out at me and i put my hand up to stop the cd and it gave me a paper cut type cut.

It really hurt, never did it again, it was an NEC 40x CD ROM drive

 

[tcsenter]

tcsenter, I wouldn't say it's completely useless, they found out what kind of RPMs it takes to shatter your average CD-R... they claimed a 56X/52X drive can get up to 30k RPMs, I really don't know the actualy numbers.

According to the article, a CD spinning at 30K RPM would correspond with a spin factor of 175x. 48x~52x CD-ROMs spin between 9000~10,000 RPM.

This is the reason Maxell announced it would not produce media rated in excess of 48x, citing concerns about the risks of media spinning in excess of 10,000 RPM. Maxell and Plextor have verified that discs can in fact 'explode' at speeds. Plextor actually builds a stronger faceplate to contain flying shards from escaping the drive.

The other half of the myth was the fact that people were getting hurt by this phenomenon, the myth claimed that shards of CD came exploding out of the case, which is something else they disproved once they found out that the shards wouldn't even penetrate the metal casing of a CDROM.

Shards were not 'penetrating' the CD-ROM enclosure or computer case, they were literally blowing off the front plate of the drive tray. This is even verified in the article:

You'd think a CD could handle 52x, right? After all, they make drives that fast.... but apparently that's not in the Playstation black-disc spec. I tried playing GranTurismo on ePSXe, and it exploded right in the drive! Shockingly, we all got hit with shards of CD (which were slowed down when they blew the faceplate off my CDROM drive), but the computer was fine, and the CDROM still works today, after dismantling it and removing all the shattered plastic.

CDFreaks also confirmed a similar event of a CD exploding in the drive and shards flying out after blowing off the faceplate.

One test, I forget where I read it, used 1mm-thick aluminum shielding around the CD to stop flying shards. The shards put numerous dents in 1mm thick aluminum shield and a few nearly penetrated. During a test without the shielding, shards hit the ceiling and caused visible damage to the ceiling surface.

I would tend to think an eye or face is not as resistant as 1-mm thick aluminum.

 

[GagHalfrunt]

Originally posted by: tcsenter
Their "myth busting" is a bit like this:

"It has been rumored that tossing a coin from a sky-scraper will develop enough velocity to kill people on the street below and penetrate automobiles. We are about to find out if tossing an object from a sky-scraper could be deadly, by rolling this 16 lb Columbia bowling ball over the edge of a 65-story building to see what she can do."

Just as one would reasonably ask 'how did a coin get to be a bowling ball?', one might reasonably ask 'how did the rotational speeds of a 52x CD-ROM get to be 30,000RPM'?

That's pure bullshit. Their penny test was completely scientific. They proved the terminal velocity of a penny and reproduced EXACTLY that velocity while trying to get the coin to penetrate ballistic gel, real flesh, concrete, asphalt, etc. They conclusively busted the myth because the terminal velocity of a penny is so low that it can NEVER hit with enough force to penetrate flesh or break bone. You just pulled that bowling ball metaphor our of your ass.

 

[Entity]

Originally posted by: GagHalfrunt

Originally posted by: tcsenter
Their "myth busting" is a bit like this:

"It has been rumored that tossing a coin from a sky-scraper will develop enough velocity to kill people on the street below and penetrate automobiles. We are about to find out if tossing an object from a sky-scraper could be deadly, by rolling this 16 lb Columbia bowling ball over the edge of a 65-story building to see what she can do."

Just as one would reasonably ask 'how did a coin get to be a bowling ball?', one might reasonably ask 'how did the rotational speeds of a 52x CD-ROM get to be 30,000RPM'?

That's pure bullshit. Their penny test was completely scientific. They proved the terminal velocity of a penny and reproduced EXACTLY that velocity while trying to get the coin to penetrate ballistic gel, real flesh, concrete, asphalt, etc. They conclusively busted the myth because the terminal velocity of a penny is so low that it can NEVER hit with enough force to penetrate flesh or break bone. You just pulled that bowling ball metaphor our of your ass.

Gag,

Tcsenter was using an analogy, to point out the discrepancies between spinning a CD at max 9k-10k RPM (as in a CD) and 30k RPM, on the end of a dremel. I don't believe he was trying to allude to any different experiments, such as the "penny test" (I've never seen the show, so I didn't even know of a penny test).

At least I think that's what he was doing.

Rob