Re: [ARSCLIST] Hard disk drives and DAT

[Don Cox <doncox@xxxxxxxxxxxxxx>]

On 31/03/07, Steven C. Barr(x) wrote:

> ----- Original Message ----- 
> From: "Don Cox" <doncox@xxxxxxxxxxxxxx>
>> I think an archival digital format that would last as long as
>> Sumerian clay tablets could be developed if the market was there.
>> 
>> It would have to use physical pits rather than dye or magnetism.
>> Possibly some kind of toughened ceramic material would be suitable.
>> 
>> Multiple layers, as on many consumer discs, would not be practical.
>> 
> And what happens if these Sumerian clay tablets get wet and stay wet
> for any length of time? Most forms of mud dissolve under those
> conditions (an argument against building "my adobe hacienda"...)

The Sumerian tablets are probably not fired, but they easily could be.

Any modern material would not be soluble in water. There are many
specialised ceramic materials used in engineering today.

>From ultrahardmaterials.com:

"There are three exceptional properties of engineering ceramics:

 (1) Their very high hardness enabling products made from them to wear less and last longer.

 (2) Their ability to operate at very high temperatures.

 (3) Their capacity to withstand very harsh and corrosive environments such as acids, alkalis and organic solvents."

The technical problem is to design a laser setup that can burn accurate
pits in a disk of such a material. This shouldn't be that much more
difficult than making a glass master disk. 

See here for a useful summary of materials:
http://www.machinedesign.com/BDE/materials/bdemat7/bdemat7_2.html

We can do better than shellac, I think. 

Regards
-- 
Don Cox
doncox@xxxxxxxxxxxxxx