23 Sep
2009
23 Sep
'09
3:04 p.m.
Tony Duell wrote:
<snip>
The conversion of the drives we did for shipment to south america
involved a different spindle pulley and a different belt. The belts
were located locally here that were equivalent to the CDC drives prior
to any conversions we did because they sold them for such a ridiculous
price.
the motors themselves were strapped easily to run on the different
frequency and voltage, as I recall. However the pulley was another
matter. The ones that we got drawings for and had duplicated were
worked from aluminum stock with quite a few processes to harden them and
form the drive surface so as not to eat the drive belt. The shape of
the pulley causes the drive belt to ride in the center when properly
done, there are no "edges" to retain it. If you have or can get
mechanical drawings of the pulley for either frequency, I'd think you
could figure out the other. In this case maybe get the 60 hz pulley,
and scale it to the 50 hz size.
There is no adjustment for spinning the disk stack at a different speed,
it still goes at the same angular rate regardless of frequency. The
electronics are running from DC which adjusting the power supply
compensates for.
The other issue is to change out muffin fans for the 60 hz model. I
don't know if you drive has 120v (or 220v) and are AC, or run off of +12.
Jim
4. Disks. Biggest problem I would imagine. RK05s
I know have different moto=
r pulleys - they're stamped 50Hz or 60Hz. I would imagine running a 50Hz un=
YEs. Same with one otuer drives too.
it on 60Hz wouldn't work=2C the heads would
never load because it would nev=
er be detected going at the correct speed. And even if they did load there =
might be air bearing issues due to incorrect speed. I have around 7 or 8 50=
Hz RK05s=2C but only 3 60Hz=2C so... does anyone have any spare 60Hz RK05 p=
Find a freind with an engineer's lathe and get a few turned up? You have
a 60Hz pulley which could be used to take measurements from
<snip>