[Coco] Disk drive question

[gene heskett]

On Wednesday, January 18, 2012 05:28:57 PM Bill Pierce did opine:

> I've tried the drives in different combos. individually as well. For the
> most part I can't even boot from a single drive except for a Level 1
> v2,00 system master boot. Seems I read somewhere long ago that the RS
> factory disks were written to in a manner that even if your drive was
> in slight miss-alignment that in most cases the disk would read. This
> was for the fact that no 2 drives are exact in alignment and they
> wanted no problems. Since the RS disk will boot and no "created" disk
> will boot, it makes me wonder about alignment.
 
Slight miss-understanding there I'd say.  And the next thing I would do is 
go get one of those shack oilers with the long tube & a cap on the end of 
the tube. Its even got a pocket clip on it. Open up the drive boxes & 
remove the drives and using some painters alcohol, not that imitation stuff 
called rubbing which is up to 70% water, and some q-tips and clean the gunk 
and old dried out lube off the shiny rods that the head carriage slides in 
and out on.  With power off, you can slide that back and forth and clean 
until they are "lox clean".  If the drive has a motor with a long spiral 
cut screw for a shaft on the back of the drive, clean that screw till its 
also shiny all the way to the bottom of the groove.  Then apply a couple 
drops of that oil and work it back and forth till its well distributed. On 
the screw drive too if the drive has one.  While you are that close to it, 
the heads can also be cleaned, but get a fresh q-tip for every time you wet 
it with the alcohol, never putting a dirty q-tip back in the alcohol to 
contaminate it.  It goes w/o saying that head cleaning s/b done gently so 
as not to spring the head suspension.

Put it all back together and see if it will work.  I'd bet the stepper 
noise the drive makes is a lot louder because it can now move easily and 
quickly from track to track, where before it was quiet, sort of ooozing 
from track to track and possibly/probably losing steps.  It _should_ be 
easily heard.  

Quiet drives are a sign of impending, if not current, trouble.

I have a tube/needle of that oil here, with about 20 drops left in it, 
pushing 25 years old & blacker than coffee from all those years of light 
exposure, but it still works.
 
What I'm using for clues here is that it won't read a disk created in it.  
If the head can slide easily enough, then it should be able to read a disk 
made in it better than any disk made in another, possibly draggy drive.  
This will not make it read a disk created before the above maintenance 
though, because that disk will probably have the tracks quite a ways out of 
kilter.

Cheers, Gene
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