10 Sector Hard sectored disks.

[Tony Duell]

>      Has anyone made any kind of jig to physically punch holes?  I am
> thinking about destroying a somewhat damaged disk drive to get enough
> parts to build a jig but wasn't sure what kind of mechanical accuracy I
> need to get the hole position jitter within spec.  I saw, somewhere out
> on the web, a persons description of hand punching the holes so I can't
> imagine the tolerance is too tight.

I'd thought of doing much the same thing. Probably raid an ex-PC 1/2 
height drive. Remove just about everything. put a punch and die in place 
of the index sensor, and a disk with 11 notches suitably-spaced in place 
of the pulley/rotor on the bottom of the spidnle. THen provide some kind 
of detent for that.

It would then just be a matter of putting a disk in, aligning the 
existing index hole with the punch, locking it to the spindle in the 
normal way and then engaging the detent in the other 10 notches, punching 
a hole each time.

As regards accuracty, you want them fairly evenly spaced becuase if 2 
holes are 2 close together they won't be enough space to find the data in 
that sector. But apart from that, it shouldn't be that critical. The same 
hole is used to synchronise the controller for both reading and writing, 
so there's no intercahnaility adjustment type of problems.

-tony