PureBasic Forums - English

Laws of physics?

Look, it's a low powered red laser... the heat generated by the laser itself is next to nothing. It is the CD Vibrating (resonating) that causes it to shatter.

Think of it like a high wind and a badly designed bridge...same principal.

as the disc spins up to speed, it begins to oscillate... the vibration alone from the resonance frequency causes the disk to shatter.

Where this urban myth about the laser getting to hot came from I'd love to know, cause if it was getting THAT hot, the disc would melt before it shatters... and in the shards of CD floating around in the drive, there would be evidence of it melting. As for the Cd's being hot when they come out of the drive... that's just from the heat generated from the electronic components and the motor. nothing more, nothing less.

besides, if a small DVD/CD-rom CD/DVD writer laser could generate such massive heat, don't you think they would be used to shoot down aircraft or something... get real

haha too many rumors.
Joachim: as lucifer said, its because of the engine and the shaking. NOT the laser.

The laser certainly dont produce enough heat to even make it a difference.

fundemental laws of physics says: Cd's fall appart because of the great speed. If you can blow up cd's by holding a lighter under them, wouldnt people be doing that all the time???

thefool wrote: Joachim: as lucifer said, its because of the engine and the shaking. NOT the laser.

Under normal reading the laser shouldn't make it hot, but when you burn a cd it might get a little hot.
We should do a scientistic test!

thefool wrote: fundemental laws of physics says: Cd's fall appart because of the great speed.

I agree with you on that.

MythBusters with their angle grinder + CD-Rom = Wrooom! Splitters deep into your meat.

These guys are just plain funny

Joakim Christiansen wrote: Under normal reading the laser shouldn't make it hot, but when you burn a cd it might get a little hot.

well, but probably not much anyway

I believe your cds come out hot because thats the temperature inside the cdrom, inside your CASE.. or that area of the case...

Burning cds in your cdrw is nothing but a laser changing the state of a surface.

cdrw's can be reverted... think about 0 and 1..

Cd's fall appart because of the great speed.

Unfortunately, this is SO easy to prove wrong. Take any CD drive out, disable the laser, bypass the governor that limits rpm and stick a CD on there and run it at full-speed (higher than any normal use and faster than any normal CD drive). Nothing will happen to your CD. Even if you adjust the drive so it is out of balance, you will not shatter a disc just from spinning it.

If you can blow up cd's by holding a lighter under them

What thread are you talking about? Nobody ever said that, anywhere. CD's explode in drives because of faulty media, or a speck of dirt. It causes an error and instead of the laser turning on and off like in normal use, it stays on as it keeps trying to read (or write) the same spot while spinning the disc at max speed. The disc overheats and falls apart. Most drives prevent against this now.

May I also mention... in all this years I never got this to happen on any of my cdroms.. nor my brother's nor any family member got this issue.. only a customer did but ! I got to know why, the care they apply to their cds is as much care as you apply to your toilet paper...!

It's like when you're going to buy a new cellphone, what you do first? check the reviews! and what do you find first? people complaining of how the antenna falls apart, how the speaker stoped working how the paint gets off so easily how the screen got broken how this how the other... PEOPLE DOES NOT CARE MUCH ABOUT THEIR STUFF! they just think something can work in any way no matter how much they kick it...

I'm not saying you dont take care of your cds or anything, but .. on most cases this is the cause of many, many problems.

I'm really careful with all my customer's hardware and all my hardware as well, but some of this guys are not... I've seen (believe it or not) a floppy disk inside a cdrom (those with auto feeders) I still laugh at that one though.

Another funny one, the pc came with the floopy drive "at fault"... so we took it appart just to find out there was 1 and a half floppy disks INSIDE! one had the metal protector all bended, the plastic all broken (you could hear the lose parts when moving/shaking the drive) I still don't know how they were able to put the other half floppy IN! (the half missing apparently was taken appart by bending the floppy up and down until it broke) incredible!, needless to say that drive couldnt be fixed. Cheaper to buy a new one we told to our customer, which was the best solution since we had used drives laying around, half price, ya know.

I have other funny ones too - However seeing how hardware is used as an old pair of pants really pisses me off..

Lyon wrote:

Cd's fall appart because of the great speed.

Unfortunately, this is SO easy to prove wrong. Take any CD drive out, disable the laser, bypass the governor that limits rpm and stick a CD on there and run it at full-speed (higher than any normal use and faster than any normal CD drive). Nothing will happen to your CD. Even if you adjust the drive so it is out of balance, you will not shatter a disc just from spinning it.

If you can blow up cd's by holding a lighter under them

What thread are you talking about? Nobody ever said that, anywhere. CD's explode in drives because of faulty media, or a speck of dirt. It causes an error and instead of the laser turning on and off like in normal use, it stays on as it keeps trying to read (or write) the same spot while spinning the disc at max speed. The disc overheats and falls apart. Most drives prevent against this now.

as dagcrack said, you cant proove anything by taking the laser out. I've never had this even occur either, so its not easy to prove wrong unless your cd's blow up all the time
no. the laser dont make any heat that you would notice. THAT is easy to proove.

thefool wrote:no. the laser dont make any heat that you would notice. THAT is easy to proove.

Then proove it!

Tried to toast my bread in my CD. No success. Crumby thing!

Wow. fun. Btw the cd is usually hot because of the spinning and friction.

Dare2 wrote:Tried to toast my bread in my CD. No success. Crumby thing!

Why don't you try stacking some CD-Rom lasers together, take a frying pan and then make yourself some tasty sunny side ups? Perhaps with bacon?

Alternatively, you could hatch some eggs, let the chickens grow to an appropriate size and then decapitate them with a Dremel powered CD, cut the best parts out (Again, gogo Gadget Dremel Disc) and cook yourself a nice curry chicken meal.

Hm... Busyness idea:
Let's sell this recipe to McDonalds. McChicken Dremel'd ^^

PS: Yeah, i know the lasers shouldn't be capable of the heating thing... But: Ever tried to shove a frying pan into a CD drive to make it spin?

chromaX wrote:Ever tried to shove a frying pan into a CD drive to make it spin?

I assume this means you have??!

Sounds like fun =P Not sure how'd you get one to fit though unless its one of those old LaserDisc drives