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From: cdold@starfish.Convergent.COM (Clarence Dold)
Newsgroups: comp.periphs
Subject: Re: Hard Disk Noise
Message-ID: <664@starfish.Convergent.COM>
Date: 26 Aug 88 18:17:16 GMT
References: <3910005@wdl1.UUCP>
Organization: Convergent Technologies, San Jose, CA
Lines: 23

From article <3910005@wdl1.UUCP>, by jeff@wdl1.UUCP (Jonathan J Jefferies):
> What information does anyone have on hard disk anti-static contacts?
>
> is that these things all make noise after the disk reaches
> 
> To further confound me, a chap down at Micropolis' repair section
> told me that Micropolis was going to do away with them because
> they were superfluos.  And in fact he removed them from disks
> 
These spindle grounding brushes may indeed by superfluous on newer drives,
and there may even be drives that don't need them where the vendor continued
to supply them, while also doing long term testing without them.
I wouldn't remove one from an existing drive, since quieting them is usually
not difficult.  I have been successful with two methods:
1) Rather than bending it back so it doesn't touch, what you need to do is
bend it forward so that it makes better contact.  The vibration is caused by
surface irregularities.  Slightly more pressure will dampen the vibration, 
making up for the wear that the carbon brush has suffered.  You will need to 
loosen either the spring, or the entire board, in order to bend it forward.
2) Our system mounts drives on edge, which heightens this noise problem.
Seagate's fix for us was to apply a small strip of adhesive backed rubber
to the spring arm, dampening the oscillation.  I've seen mention on the 
net of using a dab of silicon rubber or contact cement for the same purpose.