Today I got back a CD where the deposited film had literally peeled away from the clear plastic disk. I’ve never seen such a failure, and of course it makes the whole lot of 100 CDs suspect.
The brand is Sony, when I bend this returned disk, I find the film literally lifting away from the plastic on close to one half of the disk. On the other half, it appears to have bonded well.
As I bend and torture other disks from the same stack, I can initially find nothing wrong. I put one in the microwave for three seconds, and the deposited material blew apart evenly looking very much like a broken pane of safety glass, the remaining material still bonded well throughout the disk.
The intensely curious armature investigator is left to suspect contamination of the blank disk BEFORE the media surface was deposited, but certainly it’s only a guess.
My experience thus far (?10+ years?) is you should suspect problems IF you find disks on sale at a large brick and mortar store that are >significantly< cheaper than the rest. The last bargain I found was not readily recognized by my drive on the first try. I found I could remove them from the drive and turn them 90 or so degrees and sooner or later the disk would be recognized, and then written to… but certainly it was best to toss them and get a good stack of disks. With the same drive the following stack of 100 disks were recognized immediately and written to the very first try, and I mean to say all 100 of them!
I’ve used friction on an adjacent area of the flawed disk, no luck in loosening the deposit, then I tried heat, not luck 🙁
So how does one disk out of a stack of 100 have a flaw like this? If you have seen this problem or know of the problem… consider letting me know. Using Google, I just haven’t found a search string that nets me much info on CD manufacturing issues, it’s just like I was the only guy seeing what appears to be a problem.
Certainly.. I haven’t ruled out the possibility this disk was exposed to something after it left here, but I think that is most unlikely, as I have run out of ideas as to how I break this bond after manufacturing.
Update: 8/30/2011 As some would guess, I couldn’t leave this problem alone and decided to continue bending, and even snapping in half more new CDs off that same package of 100 disks. Finally, I bent one and noted a wave of media film lifting from that plastic disk, and just like the first, it was loose on a portion of the disk, but well bonded on the other half of the disk.
With that note, I came up with the theory that this disk came off a ‘Gang’ production line, and perhaps every 6th or 8th disk is defective? Of course the theory remains that there is some kind of contamination on the plastic disk, and when the film is deposited; it doesn’t bond properly to the contaminated area.
It causes me to reflect on other problems in production lines I’ve heard of… sometimes a new worker decides to fix what he thinks is a problem with unapproved methods… maybe a shot of WD40 on some disk handling mechanism? Who knows, but now it’s time to trash the whole pile of disks 🙁
New add to this post 08/30/2011 13:30 Pacific Time
I decided to call Sony, maybe their QC folks would be interested. I was fairly impressed how quickly I was directed to the division who handled CDR concerns.
I was given a place in Texas to send the remainder of the CDRs, and I was instructed to include my receipt from purchase. Reference # E51637622 was what I was given to include. they were purchased by my Daughter, and I failed to keep track of the receipt, likely in soe pile here somewhere, but how much effort will I put into finding it?
I was thinking how much I appreciated my customer bringing this to my attention. Just how many additional flaky disks might I have sent, and how many customers might I have disappointed? I’m going to send them the rest of the disks and see what happens, perhaps they’ll send me replacements, or perhaps they’ll encourage me to buy another brand. I’ll post the results here. And yes.. I will send them the one you see at the top of the page.