What Classic Computer are All About - A Lovers

From: jpero_at_mail.cgo.wave.ca <(jpero_at_mail.cgo.wave.ca)>
Date: Tue Jul 15 07:59:38 1997


I gently disagree with this assertion that ST251 series is good than
ST225 series. I got too many dead ST251 series compared to ST225's
due to weaker structral design, pushed design by driving steppers too
hard byond 40ms average and not as rugged as ST225's.
I noticed the relationship between higher stepping rate and
terrible high failure rate on many hard drives such as ST251's,
Miniscribes and early 40meg western digital drives compared to
very slow stepping rate on most drives did last long time byond its
goal set by designers. If one wants faster seeking time, go voice
coil! I am dreaming wishing that ST251 drive was fitted with voice
coil instead of stepper and better motor design...sigh.

Those ST225, ST250 are really best consumer's drives and ST251 series
might be a mistake at cutting corners well as ST277, ST296 are same

I wished that segate designed ST251 case
more rugged and used internal spindle motor with bearings on outside
and one screw on top of cover to stablize the motor from top. Then
this ST251's would be possible to be expanded to 100 or 120 size
reliably. Whole problem was that design of this ST251 spindle motor
is ill-designed to begin with in my opinion: Trying to fit all the
coils and one bearing INSIDE that spindle results in weak axle that
gets bent easily due to this design and the bearings failure rate on
this one is high too.

Recently I pulled this ST225 out of dumpter and fixed
up the XT with this hd and LLF'ed it. Gave whole thing to poor guy
to use vax at college. Still works.

I tore down all kinds of drives from old and 3 years old types for
post-failure analysis which gave pretty good info for me.

> ->X-Sender: cerebral_at_michianatoday.com

> First off why bother withg the st225s? They are slow (st251s are
Snip! Tales of positive things about cooling...
> If the fan isn't noisy it isn't moving enough
> air past them, seriously!
Actually, all drives old and new benefits from cooling and boards
likes the flowing cooling air.

> Also if they are in the smae box as all the
> other hardware they raise the other components temperature lowering their
> life. Heat is not your friend, this is why computer rooms are air
> conditioned an usuialy under 70 degrees F.
We have no choice as many does not have AC so they ran in warm air
but if you are careful, enough fans to make hurriance out of it and
put a fan or two on monitor as well. My 17" needs two otherwise the
HOT transistor will pop again. ARRGgghhh.

> Allison
Received on Tue Jul 15 1997 - 07:59:38 BST

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