Question re: 8" drive form-factor

[Steven Hirsch]

On Wed, 3 Jun 2009, Eric Smith wrote:

> Steven Hirsch wrote:
>> Here's a strange one:  I recently acquired two Shugart 851 drives from 
>> another cctech-er.  They were in nice shape and operate fine.  The weird 
>> part is their form-factor.
>> 
>> I have 8 or 10 other 8" drives in my collection, both half-height and 
>> full-height, including two other 851 Shugarts.  All of these are 8.5" wide, 
>> with faceplate and frame being exactly the same size.
>> 
>> These two "new" Shugart units are _9.5"_ wide at the faceplate and require 
>> a clearance of about 9-1/8" for the frame.  Can anyone explain this odd 
>> sizing?  Were they perhaps manufactured against an earlier standard?
>
> IIRC, the "R" suffix drives are intended to be rack-mounted in pairs.  I have 
> no idea, though, how that could be better than using the standard-width 
> drives since either way they're going to need some mounting hardware.

I found the OEM manual on bitsavers and it's actually the 'R' model that 
matches what I believed to the industry form-factor of 8.5" width.  The 
"standard" (non-R) model is 9.5" wide.  Odd standard, since I've never 
seen another 8" drive that size.

Always something to learn!



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