Re: So much for an injury free year, lol and SRSG Hard drives

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>



Tesla list wrote:
> 
> Original poster: "Christopher Boden by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <chrisboden-at-hotmail-dot-com>
> 
> The DAY after I sent an email to an MD on the list mentioning how long it's
> been since I had an injury.......I drop a 30 pound hard drive magnet
> assembly off the workbench....and directly onto my big toe.
> 
> Fortunately the swelling forbids me from putting my foot in my mouth ;)
> 
> Now to the reason I was tinkering wth the drive in the first place.
> 
> Along with the semi-trailer of AS-400 mainframe we got a few IBM antiques,
> some of them are hard drives that have 14+" plattens and use SERIOUS
> belt-driven motors.
> 
> 1. Are these motors sync?

They may very well be synchronous, but they might also be DC servos.
Typically drives spin at 1800 or 3600 RPM, which makes sync likely.
However, old IBM mainframes ran at 315 Hz or something like that (made
power supplies lighter and cheaper, and since you had to have a motor
generator type UPS anyway, it didn't cost anything.  I heard that IBM used
something other than 400Hz so that it would be harder for competitors to
make "plug compatible" equipment.. Crays used 400 Hz (probably because
Seymour liked using surplus).


> 
> 2. Thoughs on making a big hard drive into a NICE big SRSG? Or even ASRG?
> 
> btw, DC motors from old tape drives (the reel to reel kind) make cracking
> good ASRG motors :)


And, excellent robot drive motors, as well.. typically 500-1000 RPM with
gobs of torque.


> 
> duck
> 
> Christopher A. Boden Geek#1
> President / C.E.O. / Alpha Geek
> The Geek Group
> www.thegeekgroup-dot-org
> Because the Geek shall inherit the Earth!
> 
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