DIY Paper Tape Punch - Mechanism diagram?

[Hugh Pyle]

I've cut Mylar tape with a Glowforge laser.  It cuts very nicely but the
alignment is a major hassle, plus you can only cut ~15" of tape which
doesn't go very far.  Not worth the effort.  If you were to build a custom
linear drive it might work.  But also very slow.

Here's a picture of a mechanical (Teletype 33) punch block.  These are
quite high-precision parts with hardened pins.  The pins drive through a
narrow gape for tape, into matching holes in the top of the block.  On the
Teletype, the drive mechanism is slow, and the punch sits quite a long way
from the single solenoid that sets up the bits.  I assume high-speed
punches have a similar block but a more direct (parallel) actuator.
https://photos.app.goo.gl/F6QZQE3tiKgiGB6c7

CuriousMarc has a good video showing this sort of punch in operation,
https://www.youtube.com/watch?v=yzulZaJbdUU&list=PL-_93BVApb5-84G5kmgfuu7TQduTMc73H&index=8



On Fri, May 1, 2020 at 12:02 AM Anders Nelson via cctalk <
cctalk at classiccmp.org> wrote:

> Hi all,
>
> I've had a paper tape reader for a while but never had a punch to make new
> tapes, and the ones i've found are not only very large but also very
> expensive. So I'm toying with the idea of making an open-source punch, but
> I can't find any detailed diagrams of how the mechanism works.
>
> I'm assuming (without any data to back it up) that there is a cam, an array
> of spring-levered pins, and horizontal spacers controlled by solenoids that
> bridge the gap between the cam and each punch pin when called for.
>
> Does anyone have insight into how reliable/fast paper tape punches work?
> --
> Anders Nelson
>
> +1 (517) 775-6129
>
> www.erogear.com
>