What I want to do
A few months ago, I taught a papercraft class at Parts & Crafts, and we went through a lot of different paper hinges, joints, and fasteners, so I tried some out on a mod of the mini foldable spectrometer (available in the store here).
Update: this design has been finalized with more detailed instructions! See step by step photos in this activity.
My attempt and results
It's tough to figure out a glue-less fastening which is also light-tight, but one way is to have double flaps. This is clearly a work in progress, but I also widened the design so it's easier to hold, and fits our wider acetate slits, and makes a wider band of spectrum, so it's easier to get a cross section.
I also found it made it wide enough to put instructions on -- I thought perhaps build instructions could go around the cutout, and usage instructions could go on the device itself -- kind of like the instructions written on the door of the Antikythera mechanism (thinking back to the talk I gave at the Open Hardware Summit a few years ago)!
(image via Wikipedia)
Here are a bunch of photos:
Questions and next steps
I think a more thorough division of instructions between construction/use as outlined above is a good next step, and further work has to be done on attempting glue-less attachments, if possible.
I'd like to see if it's possible to make it easier to print onto stiff non-black paper, and just blacken the back (by printing black ink, or painting it). This'd make it easier to reproduce.
Why I'm interested
This design's been around a while, but there's still room for improvement! It's a great onboarding opportunity too.
To build one yourself, download the PDF here, print it onto some thick paper (you can also do it on thinner paper and trace it) cut it out and piece it together:
Update: see newest design files at bottom of this comment thread!