This is a circuit made with the vinylcutter. The project involved designing the circuit, cutting it out of copper sticker, glueing it on paper, stuffing the electronic components and programming the micro controller to make the LEDs light up in a pattern. Step by step instructions how to do this will follow soon, here are some pictures of the process.
Step 1: Designing the Circuit
The design was based on the Charlieplexing array output board from the Fab Academy. These files provided a good basis to start from. I designed the circuit that contains an ATtiny 44 micro controller in Eagle.
Step 2: Cutting the Circuit
The circuit was cut with a vinyl cutter. Cutting copper is not very easy so here some tips and tricks.
For the design:
- Make as many rounded curves as possible since the knife is not so good at cutting 90 degree angles
- Take as much space as possible between the components
- Make the copper lines as thick as possible
- if you have a lot of space between thin lines, draw some extra rectangle on the copper that will be weeded off afterwards. It is easier to tear off little pieces of copper at the time.
- I used force 40 and speed 1 cm/s.
- The copper comes on a sticker roll. To cut sharp straight lines you have to glue a piece of the copper sticker to a rigid cardboard first before placing it into the vinyl cutter.
- When the knife is running, some traces already start to curl up from the circuit and might be hit by the knife as it moves over. If this happens pause the machine and press the pieces back to the surface with tweezers.
Step 3: Weeding the Copper
Place a piece of transfer paper on the copper as soon as the machine is done, and while the copper is still glued to the cardboard. If you wait too long all the traces will start to curl up. Then take the copper sheet off the cardboard, and pull off the backside of the sticker. Now you can start weeding the copper that is not needed in the circuit, leaving only the traces behind on the transfer paper.
Step 4: Transfer the Copper
Now you can place the transfer paper onto a surface, like paper, acrylic, or whatever you like. Then stuff the components - be careful with the heat of the soldering iron on the surface material