Silhouette Cut Public Lab Mobile Spectrometer

Introduction: Silhouette Cut Public Lab Mobile Spectrometer

I am a fan of spectrometers. These instruments are used in industry and science to find out about compositions and of things(liquids, stars, leds, compact fluorescent tubes) through the light they emit or absorb. Typically, they are expensive (1000's of $£) because of their precision, but there also affordable useful versions for use in DIY Biology or citizen science.

Public lab has developed a series of these spectrometers, as well as software that can be used in browser.

The one I am interested in is the cheapest one, the Foldable Mini-Spectrometer. You can Build your own with a printer, scissors, some card, tape/glue and a blank dvd. I used the "Build your own" page as a reference, and if there s any directions you find unclear, they probably said it better.

I am especially grateful that they release all their stuff under a Creative Commons Attribution-ShareAlike 3.0 Unported License with Hardware designs released under the CERN Open Hardware License 1.1.

I had built one in the past out of white paper, but it was flimsy and the white paper made it too reflective. I hadn't thought about it again until our makerspace ( got to play with a Silhouette portrait.

I quickly realized it would be easier to cut with the portrait. I did one cut (of the outline and the windows). It still needed folding using a ruler and pencil. Then I had the bright idea to use the perforation setting to make folding easier.

The final change was to extend the window to make it easier to encapsulate the piece of dvd.

This instructable provides the file (in the silhouette studio software format) for cutting, and instructions for assembling and using.

Have fun.

Step 1: What You Will Need....

To make the spectrometer you will need:

  • black card
  • blank dvd
  • scalpel/scissors
  • things for fixing : glue, tape(clear and black)
  • optional:clamp for glue(I am using a heatsink clip)
  • wondering what's the cork for? keeping the scalpel safe

I have been using the silhouette portrait with its studio software.

Step 2: Cutting Out the Spectrophotometer Sheet

Setting up for cutting.

  1. setting: card(plain)
  2. set the cutting blade to 4 on the machine
  3. use the (supplied) backing sheet for the card
  4. turn on the silhouette
  5. load the backing sheet by pushing it to the roller
  6. hit the top button (looks like a graphed clipboard) on the machine. [steps 5-6 in the 2x speed 1st video]
  7. then [send to silhouette] from the program
  8. away it goes. [in the 8x speed second video]
  9. hit the eject button
  10. peel the card off the backing sheet

Step 3: Assembly

  • fold as shown in the spectrograph diagram
  • leave the square window till last
  • tape all the other folds
  • look into the resulting box at the slit at the end.
    1. is it free of any stray card? use the scalpel to clear it.
    2. are there any light leaks(apart from the slit)? use the black electrical tape to seal it?
  • Now the interesting bit.
    1. take the dvd
    2. cut a quarter of it off with the scissors
    3. trim a 2cm wide bit
    4. keep this
    5. separate the two layers of the dvd with the scalpel
    6. keep the clear layer
      1. want rainbow to go in the same direction as the slit.
    8. glue the first aperture down
    9. now place the dvd layer over the aperture and fix it down
    10. secure with the final flap

Step 4: Using It

Three ways to view

  • use your eyes
    • put the side with the piece of dvd up to your eye.
    • look through while moving it near a indoor light source. Old style tungsten should give a rainbow, while fluorescent will have a few bands, and leds only a few)
  • to make a photograph
  • tape the spectrometer to a phone
  • tape the spectometer to your webcam

Step 5: Summed Up

Can we make a spectrometer with a plotter cutter? Yes

Used it on android phone and windows laptop.

Further ideas

-rather than perforations, scoring might work

-change the size of the incoming slit

-container/cuvette holder to look at aqueous samples.

P.S. this is my first instructable, constructive comments please.

Step 6: Further Resources

1 Person Made This Project!


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    Stick It Challenge
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6 years ago

Thanks for the Silhouette info. Now for an actual Spectrometer question!

I made this using my Portrait and the only cardstock I had handy: pink. After assembly, I covered the outside in black electrical tape to block light. I tried to follow the instructions to make the grating from a DVD-R, and I think it worked.

However, I don't see a spectrum! Since I'm a complete noob at this, I don't know where to look or what to look for. I have looked all over the PublicLab site, but can't seem to find a picture of anyone using this device with the naked eye. At what angle and where should I look for the spectrum? I've tried pointing the slit at everything from the sun to a candle. Looking thru the grating, I can see the light slot, I can see the light hitting the inside surface of the tube (as a nice line), but I don't see a spectrum. Can you give me some direction? Thanks for any help.


Reply 4 years ago

Was the grating orientated the right way?


Reply 4 years ago

Yes, if I remember right. I think I was looking in the wrong place. Anyway, I stopped working with it and took another approach. See my stuff on Hack-A-Day.


6 years ago

Very nice work! And a valuable pointer to the Public Lab site. Thank you!

I'm curious about how you made the pattern for the Silhouette. Did you use the their tools to extract the image or did you redraw it? If you used their tools to extract, I'd love to know more about the details of how you did it and what you thought of the process. I'm planning to use those tools to get outlines for some paper structures so I don't have to cut up the book they are in.


Reply 6 years ago

I tried a few the end I think I used inksCape to open the pdf and puzroduce something that can be imported into the cutter software.
Then it was tracing....different patterns for cut and scoring.