On 25 Apr at 22:30, Steve Bennett of 3:635/506 wrote to Chris Maddock:
CM>> can be "squeezed" between the head and the disk surface. You would be
CM>> amazed at how hard it is to get the surfaces to touch when the disk is
SB> Nope, very easy...just get a minute particle of dust :-)  Just ask my
SB> old 40 Mb hard disk which collapsed spectacularly quickly .
I was talking about the air molecules being trapped between the surfaces of 
the disk and head, not dust. What you said is basically correct though. The 
distance during normal operation conditions between the two is approx 3-5 
microns. A *small* bit of "dust" is something in the order of 15 microns.
In a nutshell, 15 into 5 goes WHACK!
SB> Not that that was caused by a virus of course...
Of course. However it is interesting for some people who think that disks 
have needles or pins or whatever that a virus can somehow manipulate.
They don't, they don't, and it can't. 
Regards,
Chris Maddock
chrism@softtech.brisnet.org.au
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