For this Intro to Fabrication assignment to create an enclosure, I chose to work on my current project in Intro to Physical Computing. I’m designing a musical instrument that you can press onto your window. When the sunlight comes out, it plays a song such as “Here Comes The Sun” by the Beatles. I’m imagining it would take the shape of an abstract sun, and made of translucent material in order to let the light in through the object as well.
Below is my current prototype.
For now I chose to use cardboard because this was my first time measuring precise holes for components, and I knew I wanted to change the shape later on. Over the next few iterations I would use yellow mat board, and then eventually yellow acrylic. Also, the back would use a suction cup or two. Eventually, I would learn to use a light sensor from Adafruit to place on the back of the object to face the outside. I’d place this behind a small plate of clear acrylic so that light can enter.
You can see I also used dowel pins instead of metal standoffs for the same reasons.
Below is an example drawing of what I have in mind.
However, by now I’ve come to the conclusion that I’d like the shape of the object to be an abstract sun, not a typical sun shape (as drawn below). Otherwise the design in total seems too on the nose… meaning each design element (the light sensor, the songs about the sun, and the shape) become too literal. Perhaps if I make the sun to be abstract like in my prototype, the total effect to be more interesting.
For now, a lot of my design decisions were determined by the size of my components. The object had to be large enough to house the microcontroller, the bread board, and the battery. Likewise, the control panel had to be large enough to accommodate the buttons and sensor.
For now, the front and inside.
Soon I would create this back piece, once I learn how to place the specialized light sensor.
Once I had a sketch in my notebook, I started putting my design into Illustrator.
Here you can see the time I took to measure each component using an analog caliper. I then used these measurements to update my Illustrator shapes to match the size of my components.
In this Illustrator file below you can see I did two things that don’t appear in my final prototype.
- Added lines to measure the distance between objects, which I later removed before printing to the laser cutter. Could I have added these to another layer in the same file, which would not have printed? Do the laser printers only print the first layer, or do they print all included layers?
- Created sides for the enclosure. However, I saved finishing these for another time so I could focus on completing the control panel. Next time I’d be ready to do measurements to create sides like the ones found in this Nixie Tube project (image below).
Nixie tube sides.
On the 50w laser cutter I used these steps to cut cardboard. The cardboard was thicker than what I used last time. This time I used auto focus! I also used 600 DPI. My other settings are below.
First time – 50/50/500
Second time – 20 / 50 / 500
Third and fourth time – 20 / 75 / 500
Three times – 20 / 75 / 500
One question I have is how much does DPI matter? The printer’s list of material settings makes adjustments based on DPI.
A major component of my control panel that did not print well is the TEXT on it…
You can hardly see it. Granted I only managed to make 9 font size fit due to limitations of my components’ sizes. However, I followed the ITP Illustrator Laser Printer tutorial on the Shop’s website which mentions how to set text. I used the color black and did nothing else as suggested. However, when I sent the file to the laser printer, I got a pop up dialog box that said it would have to turn the font into an object.
Why did the text etching become white? Whereas the sun etching became black?
What settings should I have used for text?
Here are a few more photos of my final prototype. My buttons aren’t flush with the holes for three reasons.
- I didn’t have the perfect height to lift my breadboard enough to match the height of my components (I used my phone to give it some height, as you can see below).
- The hole I cut for the on/off button wasn’t big enough!
- My jumper wires are quite long and create additional unnecessary height because they aren’t cut to be flush with the board and microcontroller yet. I’ll do this once I’m sure my circuit is final!
In the future, you would also see my battery and if being used, my USB to microntroller cable.
Below phone is being used to give my breadboard height. My dowel pins look a little wonky.