Cracks in a disc.

[bizzybody]

I just burned a DVD-R and noticed what looks like several semi-circular cracks in the plastic on the data side. Never have seen that before.

I didn't inspect the disc before putting it in the burner so I don't know if they were already there. The disc I burned before is fine and the next blank on the spindle (2nd from the bottom) is also fine.

It verified OK and I was able to copy everything back from the disc without error. I'd deleted the files after burning. (Which is better than deleting *before* burning, with it looks like I did for three discs, dagnabit.)

I guess to be safe the cracked looking one ought to go through the shredder and another copy burned.

I've had no luck finding info on such cracking, all that turns up is you know what sort of software to do less than legal things to other software.

[VegasBud]

bizzybody,

I've never seen "semi-circular cracks" either...and I hope I never do. I guess that means I should congratulate you (for experiencing something unique) and offer my condolences (for your loss) at the same time.

Cracks are never good. They interfere with reading/writing of the data on the disk, and sooner or later expose the recording layer to the ambient air. Once that happens, it's just a question of whether the reflective layer or the dye is going to go first. Either way, the longevity of the disk is pretty well shot.

Definitely you should reburn.

Out of curiosity, what program were you using to burn the disk (when it verified despite being cracked)? It doesn't really matter at this point, but I'm wondering whether it verified because the unreadable data under the cracks was offset by the error correction, of if the burning program wasn't really doing a byte for byte comparison for verification.

[bizzybody]

Nero 9. I finally "upgraded" from 7.x.x because that version was having lots of trouble with a batch of HP 2.4x DVD+R DL discs. If the data was bad, XP wouldn't have copied it back from the disc. Never have had a disc where Nero failed it on verification that I was able to copy the bad files back.

The main problem with Nero is it still limits the number of characters it'll allow in the volume label for video DVDs. Hello? Have they not noticed the commercially produced DVDs with really long volume names that work just fine?

I've tried some of the free burning apps and none would even begin to write to these HP discs, either wouldn't do anything or come up with some "error" and quit or refused to recognize the disc is in the drive.

[tomwil]

I'd be worried about the disc shattering while spinning in the drive.

Mythbusters CD shattering

[jman98]

Nero 9. I finally "upgraded" from 7.x.x because that version was having lots of trouble with a batch of HP 2.4x DVD+R DL discs. If the data was bad, XP wouldn't have copied it back from the disc. Never have had a disc where Nero failed it on verification that I was able to copy the bad files back.

The main problem with Nero is it still limits the number of characters it'll allow in the volume label for video DVDs. Hello? Have they not noticed the commercially produced DVDs with really long volume names that work just fine?

I've tried some of the free burning apps and none would even begin to write to these HP discs, either wouldn't do anything or come up with some "error" and quit or refused to recognize the disc is in the drive.

We recommend ImgBurn around here for DVD burning. It works - period. Nero does some stupid completely unnecessary stuff when burning DVDs like it puts the BUP and IFOs in the same block, which completely negates the entire reason that BUPs exist in the first place. Nero is NOT recommended for DVD burning, but it's OK for burning audio CDs and data files. Anything else - you should use ImgBurn.

How exactly are you using Nero? Through that Nero Express GUI? That defaults to, well, "dumbass options" that work for most inexperienced users. If you start Nero Burning ROM you can change the length of the characters it writes to something like 31. That's still a limit for Joliet or ISO (I don't remember which), but it's better than the default. I suspect that you are using Nero through the GUI, and yes, you have almost no control there over how Nero works. But that's not Nero's fault. That's your fault for not using the Burning ROM option and knowing how to change the settings.

Why are you using HP discs? They are low quality. The ONLY DL media worth buying is Verbatim DVD+R DL period. You are wasting your money on HP DL discs. Please don't come back crying when they stop working a year or two from now. And we don't want to hear about your bad burns either.

[bizzybody]

That's your fault for not using the Burning ROM option and knowing how to change the settings.

You shouldn't make such dumbass accusations. I have over 26 years experience with computers. I've five different PCs with various versions of Windows, so I have a lot of hardware to try things on.

Nero Express? Hell no! I've been using Nero almost from its first release. I wish they'd give up on the bloatware and release a version that's just a burning program like it used to be.

The only way I've been able to get Nero to put a longer volume name on a DVD is by first making an ISO then changing it with DVD Decrypter, then burning the ISO.

I got four 15 disc spindles of the HP discs for $4.97 each on clearance. Single layer media ought to be in the minority on store shelves by now, especially since it's been what, five years since any new single layer burner was sold. But we're stuck with a choice of hyper overpriced 3 and 5 packs of DL in jewel cases or little 15 or 20 disc spindles at $2 a disc. Wal-Mart could cure that in a week simply by ordering a billion DL discs and selling 50 disc spindles in all their stores.

ImgBurn is one of the apps I tried which wouldn't work. IIRC it created a TOC with all the files shown as zero size. InfraRecorder spits out some bogus "error" message with DL media, even the high priced ones I've tried. It won't even create the temporary image file for a DL burn and it will not burn at top speeds on any media in any drive I've tried it with.

Zero coasters so far on SL or DL with Nero 9. It works just fine for most things.

[budz]

^^^^as jman98 mentions you're using low grade media.... which will degrade over a period of time.....nuff said....NERO is also crappy to use...but to each's own.....VERBATIM DVD+R DL media is the best brand which is reliable for DL....Just my 2 freaking cents!

[VegasBud]

bizzybody,

I don't think people are trying to be mean to you. It's just that you're saying HP DL media works fine with nero, which I have no doubt is an honest assessment of your personal experience. However, the HP DL media appears to be CMC MAG D01, which is pretty low quality, and nero has some "quirks" which make it a poor choice for dvd-video disks (especially dual layer).

That combination may work well for you, but for most people the results would be very bad...so bad that it could trigger a new wave of people asking questions (here) about why they're getting coasters when using low quality media and nero to burn dvd-video. It's kind of like a forest fire that way...the members here pitch in to help put out the fire, but if effort isn't put into hosing down the hot spots, the forest fire may re-ignite. After years of fighting this particular fire, you can't blame the firefighters if some of them are particularly aggressive in applying large amounts of cold water to any hot spot that threatens to trigger a flare-up.

Actually, I'm one of the firefighters. In this thread, I have two posts...one post which details the problems areas when burning dvd-video with nero, and another post which describes how to test for one of the problems, so you can verify the existence of the problem with your own eyes. I've also spent far too much money on bad media. I would not wish my experience on anyone. It really is quite simple...if you use good media, you don't have problems, nor do you end up with scrap (which increases the cost-per-useable-disk). I would hate to think how much it cost me to learn that one simple thing.

[VegasBud]

tomwil,

The Mythbusters can always be relied on to push things to catastrophic failure (as in "BOOM"), which is part of their charm. To get the "BOOM" footage in this case, they were no longer using a dvd drive, and had moved on to using a high speed router. While doing so makes for solid entertainment, it's not really representative of what generally happens in a dvd drive. In the video you linked to, the most likely cause of the catastrophic failures was the horrendous wobble.

Having said that, I have seen the aftermath (on one occasion) from a dvd flying apart inside a dvd drive. The drive was mortally wounded, but the shrapnel was entirely contained by the drive casing. The person responsible did admit that the disk was cracked.

[lordsmurf]

Scan the disc so I can see the cracks.
I've seen a lot of things. Would be unusual to show me something new.

[cal_tony]

I was interested enough to watch the Utube video of the mythbusters and I also thought that the use of a router was overkill especially when they showed the distortion of the disk in slow motion just before it let loose.

However I do have a question about the small cracks that radiate out from the spindle that are caused by the press fit from the original commercial boxes.
Is there a rule about using these? Use once on an old drive and make a copy and never use again? Or are they okay to use?

Tony

[VegasBud]

cal_tony,

I can't help you with a "rule", but I can provide some observations.

The hub (the center of the disk) is the part of the disk which is most subjected to stress. It's a given that any crack originating at the hub will lengthen, and that at some point the disk will lose enough structural integrity to be able to withstand the stresses, which will result in the disk fracturing (shattering, exploding, etc.). However, outside of a laboratory, there's no way to predict how long it will take to go from a "small" crack at the hub to catastrophic failure. Major contributing factors would be the crack characteristics, the rotational speed when being used, and the degree (and frequency) of acceleration/deceleration of the disk when being used. If the disk is a dvd-video disk, and is just being played (at 1x) on an infrequent basis, it's (probably) going to last longer than a data disk being randomly accessed at 16x on a frequent basis.

If you really want to dig into the details, there's a paper titled "Fracture Identification and Prevention of a High-Speed Optical Disk With a Crack" which might be of interest. At least at this point in time, you can get a pdf of the paper (for free) by clicking here.

[cal_tony]

@VegasBud

Thanks for the info. I looked thru it. Later, I will read all of it.

Tony

[classfour]

I've seen DVDs crack at the hub - typically not a spiral break, but from the center out. I did have one crack in two on one side. I've had rentals with cracks in them from the get go. Oddly, I've yet to see a recordable with the problem - it must be exclusive to pressed media.

I suspect the rental had a tough life - no other reason.