30 Mar
2010
30 Mar
'10
7:57 a.m.
I just finished a project using stepper motors and a PIC processor to
drive the whole thing. Aside from defining the parameters (and debugging
my mistakes), it was pretty easy to do. I used a Ramsey Stepper Motor
driver kit to drive a 200 step/rev floppy disk drive motor along with a
16F84A PIC processor to control it, and it worked great.
Using a sharpie to just mark the hole location sounds like it would be
really easy to do. Anyone know the permissible hole tolerances on hard
sector floppies?
If using a laser, what power would be required to cut the holes and what
kind of laser? I currently have a 35W IR laser that could be more than a
bit dangerous without proper safety precautions ... I've kind of gotten
used to eyesight :)!
People have
been known to make their own 5 1/4" hard-sectored disks. I don't
> remember the details, but the basic idea was to take a 5 1/4" disk drive to
> hold the disk, make an index wheel for the holes, add a hole punch, and then
> just add time.
One thought I had was to take an old 5.25" floppy frame (say an
SA400), replace the DC motor with a stepper, mount a floppy disc, then
drive the rotation so many steps (you'd have to calculate/measure the
pulley ratio), then punch the media. Simple stepper drivers are
inexpensive to buy ($20, say) or make and easy to drive from a
microcontroller or parallel port (or even 555, if you wanted to do it
"old school"). It'd be even "better" to have a laser make the
hole,
but that's a lot of power to be squirting around - punches for mylar
rarely make holes in someone's retina.
If it's too tricky to mount the punch or die in the floppy frame, one
could pulse the media around as required and dot the spot with a
sharpie, then eject the floppy and punch the holes by hand.
-ethan