This is a very cool multi-colored butterfly I made - requires minimal parts and programming!
Aside from the butterfly itself - it shows some very cool techniques where you can make your own PCBs on a silhouette home cutter out of regularly commercially available copper tape - which can be placed onto any type of surface!
Obviously - something like this could be easily created via a commercially made printed circuit board - but if you want to spare the expense of having one made, you want to create LED patterns over a non-standard material (like a mirror or window, rather than a fiberglass PCB) - or even something with a curved surface - this method can be used to cheaply adhere the copper PCB traces onto just about any kind of surface.
This is easily done for things like LEDs which have large lead pitches - but gets harder as you use more fine, smaller pitched parts. So this technique may be used selectively - i.e. use an off-the-shelf board (Arduino) as a computer, and the home-cut copper etches for places where you want extreme customization in placing LEDs.
I used the following to create this project:

- A Silhouette Cameo personal vinyl/paper cutter - for creating PCB
- Arduino UNO - used as an in-circuit programmer
- Laser cutter for parts (wood - acrylic - anything) (you can use something else if you have no laser)

Actual parts are:

- A $1 ATTiny75 processor
- 22 NeoPixels - (serially controlled, tri-color LEDs)
- 2x3 header
- Copper Foil

All software was done in Arduino IDE - using Adafruit NeoPixel libraries, and ATTiny libaries from Board Manager.
There are two fundamental ways to approach this:
Easy Way: I have my own board (like an Arduino) that I am going to use to control the LEDs. I am only going to create a PCB for the LEDs - and hook that to my arduino.
Harder (and cheaper) Way: I am going to do eveything 100% myself. I don’t need an Arduino, and am instead going to use a $1 ATTiny85. This is harder because doing all the fine-pitched art on a Silouette or CriCut-type vinyl cutter is harder.”

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