>Mike S. posted this:
>
>> Gene E. Bloch wrote:
>>
>>> Skybuck Flying posted this:
>>>
>>>> Sony for example sells dvd's which come in a "cake" package.
>>>>
>>>> This means multiple dvd discs are stacked on top of each other
>>>> without any further protection except the cake around them.
...
>>> It must be the gravity. Stacking DVD discs must be bad.
...
>>> The special dvd jewel cases/enclosures could be ment to prevent that from
>>>> happening. Without the special dvd jewel cases the dvd's would be exposed
>>>> to too much pressure ?!?
>>>>
>>>> So it's time to ask the following question:
>>>>
>>>> How much pressure/weight can a DVD take before it loses it's data ?
>>> The hub of a CD or DVD is thicker than the recordable area. When you
>>> stack the disks, only the hubs are touching.
>>
>> Usually, but not always. I have a cake box of inkjet-printable Verbatim
>> DVD-R which is specifically marked as not having a raised hub. The discs
>> are flat.
>
>Thanks for the warning :-)
>
>So much for relying on (what I thought was) a spec...
Are those inkjet-printable DVD-Rs flat on both sides? Although IIRC the spec calls for a raised hub on both sides, I can see a manufacturer making a nonstandard product so that the printer has a flat surface to work with, but I would have to assume that it still has a raised (lowered? ) hub on the bottom. I have designed a fair amount of DVD and CD manufacturing equipment, and the basic idea of grabbing a disc off of one spindle, processing it, and putting it on another spindle is pretty much universal.