DOS feature on formatting disk

From: Bjørn Vermo <>
Date: Wed Jan 19 03:28:17 2005

On Tue, 18 Jan 2005 09:35:01 -0800 (PST), Dwight K. Elvey
<> wrote:

> Hi
> DOS has an irritating feature when asked to format
> a disk. If track 0 is partially readable it will
> fail to format, even if you use the /u option.
> I've been moving data from one machine to another
> and the source machine has a flaky drive. It sometimes
> trashes track 0.

Any OS / file system has problems if track 0 is really bad, especially if
sector 0 is bad.
I have been able to "fix" old IBM 10MB drives by adjusting the physical
end stop by a fraction of a trackwidth.
On these drives, there is a small bumper on the outside that the external
part of the actuator bumps against when you send the drive a command to
recalibrate or locate to cylinder zero. Adding a very thin sliver of metal
will move the calibration point by a fraction of a track. If you try this,
you may be able to find a spot where you can successfully format the first

Received on Wed Jan 19 2005 - 03:28:17 GMT

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