new punch

[glenn.f...@gmail.com]

For those interested in keeping their old H17 drives going there’s been some nice progress in developing a low-cost, reliable punch to convert soft-sectored (single index hole) 5.25” media into hard-sectored. This new approach uses relatively inexpensive 2.5mm paper punch drills available from Amazon: https://a.co/d/8nzSevQ and a 3-D printed guide for punching the holes. Initial results have been positive with no “hanging chad” problems due to the hollow-bit approach used by the punch.  We’re still experimenting, but this approach seems to offer the promise of significantly improving the supply of hard-sectored media. The punch is based on a design posted by @briskspirit on the SEBHC Discord group.

 

Once this is fleshed out there will be more information on how to build or obtain one of these punches for your own experimentation

 

• Glenn

 

[Gene Buckle]

That's neat. Are you building a rig that will clock the disk based on the index hole? It would be kind of fun to see a stepper driven model with
a servo that would drive a lobe to do the punch op... :D

g.

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[Glenn Roberts]

That would be cool!

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> On Oct 13, 2025, at 9:45 AM, Gene Buckle <ge...@deltasoft.com> wrote:
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[Gene Buckle]

You could use a rotary encoder to control the stepper in order to spin
the cookie to clock the index hole at the start point, then insert a
test pin that would validate the clocking.  Hit go and hard sector holes
ensue. ;)

If you make the clocking pin metal, you could use it as a validation
switch so the Arduino wouldn't start punching holes until the clocking
was validated.

g.