s<   Do you mean open the HDA?!?! Do you have a class 100 clean room

Yes.  Or was I explicit enough.

This is a time proven way to get cranky micropolus 1325s (and friends)
working as the head carriage get stuck to a rubber stop bumper.

I have three I've done major surgery on the HDAs and all still run, the
oldest is now 3 years post surgery.  Granted I've taken a little care to 
keep the area clear but I severely doubt anything approaching class 100.

Though building a class 100 clean room is not that hard.  All that's 
needed is a 200cfm blower, a suitable filter(HEPA) and some 6mil poly 
to surround the output as a curtain.  A bench sized area would be 
trivial.

The HDA has an internal filter to gather up the dusts when it spins up.

I also have a st506 that is about 15years old that I made a lucite cover 
for show, it's been very reliable.  It's the difference between book and 
actual practice.  At anything over 1000rpm any material on the disk 
including airflow is spun to the periphery and impinges on the case or 
in the case of HDAs directed through a filter.  In a factory situation 
the cavity is cleaned several times during assembly and later purged with 
dry N2 to minimize any dusts inside the cavity, as a practice to insure 
good yeild.

<500 such particles per minute, suggesting that trying to get by without 
<special facility is impossible.

Your suggesting zip/jaz drives, RA60s, RK0Xs, RM0Xs, and RL0Xs are not 
possible too as they are similar technology. 


Allison