Teletype paper tape splicing and alignment guide jig by 1944GPW

Last crawled date: 3 years ago

If you are into vintage computing then you may find this little jig useful. It facilitates the cutting of sharp, straight cuts across 1" wide 8-level ASCII Teletype paper tape.
This makes it easier to trim, splice or join sections of paper tape for repair so it lessens jamming and tearing when run through a paper tape reader such as an ASR33, PC05, OP-80A, EECO CNC or whatever other paper tape reader you have.
Use
Place the tape to be cut onto the jig with the centre blade slot where you require cutting. Press down firmly until the tape feed sprocket holes are seated properly on the sprocket pins. Using a single edge razor blade positioned in the centre slot (make sure it is SHARP) press on one edgeand then right through. It should give a crisp snapping noise as it cuts. You could also use an X-acto #11 blade in a hobby knife.
Generating
The OpenSCAD parametric script is included so you can tweak it if you like. For instance to make it longer, just bump the PINS value. Although a 5-level Baudot RTTY paper tape will fit fine on the guide as it is, you can change the LEVEL variable from 8 (ASCII 8-level) to 5 (Baudot 5-level) specifically if you desire.
Printing
PLA is ideal. Infill was 25% but could be anywhere from there up to 100%. Printed with brim only, no raft. I touched the pins and cutting groove with a black permanent marker to improve locating visibility
Making Teletype paper tape without a punch
If you don't have an actual vintage paper tape punch you can use a home stencil cutting machine along with my PTAP2DXF program to make paper tape that is fully functional (as used in this thing's photo).
For more info visit https://github.com/1944GPW/ptap2dxf