Public Lab Research note


This is an attempt to build an upgrade.

Scissors-only build of wider papercraft spectrometer

by warren | July 06, 2017 16:42 06 Jul 16:42 | #14625 | #14625

I worked a bit on an easier-to-cut-with-scissors process for this modification to the papercraft spectrometer (vs. the version in the store now); since this is the "introductory" design intended to onboard newcomers to the project, I'm looking for ways to make it as easy as possible to build. Here are the photos!

Update: this design has been finalized with more detailed instructions! See step by step photos in this activity.

(Older version:) And here's the PDF i worked from: https://i.publiclab.org/system/images/photos/000/015/953/original/foldable-2.0.1.pdf

I tried adapting it a bit for being cut out with only scissors -- the main issues are a) cutting out windows (you have to poke a hole, and it's a tough cut), and b) making a narrow slit for the light (since we won't have the ones printed on film that we ship with our kits).

Cut along solid lines around the outer edge of the spectrometer.

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Use a pencil to punch a small hole in the "flap" where the DVD will sit. Then carefully cut it out and discard it. Using a box knife can make this step much easier, but be careful!

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(Here's where we deviate from the printed design to make it easier for scissors only!)

Now, cut two 1 inch wide areas to cross the zone marked out for a "slit" -- as shown here: image description

Carefully tape or glue a square piece of spare paper over one of the new areas as shown, leaving a hairline gap through which you can see light. The narrower this gap the better, but some light must make it through.

Note that if you print or paint black ink over the reverse side, the interior of the spectrometer will be darker; we left that out since it would make it harder to photograph.

Use a butter knife, tweezers, or the wrong side of a scissor blade at a low angle to crease along the dotted lines. This will make it easier to fold cleanly.

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Now, take a DVD-R and (really!) cut into it as you would cut a wide pizza slice.

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Once you have your slice, carefully peel the opaque layer away from the purplish transparent layer; keep the transparent one. Try to get a piece with no foil on it, especially near the outer edge.

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Firmly tape the slice onto the reverse (blank) side of the large hole you cut earlier.

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Fold down (mountain) along the dotted lines, and up (valley) along the dashed lines, leaving the labeling on the outside.

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Now, fold the smaller side over the larger side and tape or glue the side shut. Tabs were provided in case you have a box knife, but you can skip these if you only have scissors. image description

Now fold over and tape down the two overlapping front flaps -- first the one you made the narrow slit on, then the other to cover and secure it.image description

Finally, you can tape down the large diagonal flap on the back. This is the surface you'll attach (tape, glue, whatever) to your smartphone or webcam. image description

Now you're ready to attach it to your phone, webcam, or Raspberry Pi camera, and calibrate it using Spectral Workbench.

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1 Comments

Posted some refinements! https://publiclab.org/notes/warren/05-04-2016/tweaks-to-foldable-mini-spectrometer-design#c17578

Making it much easier to do with scissors.

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