Picture of Cheshire Cat Pumpkin animated with LEDs
How to carve a Cheshire cat pumpkin with LEDs animated by an Arduino.

The smile of the cat first lights up white, then the eyes green, followed by the body lighting up blue starting at the tail and moving up to the ears.

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Step 1: Materials and Tools

Picture of Materials and Tools
- X-Acto knife
- Paring knife
- Various small drill bits
- Soldering Iron
- Large pin

- Pumpkin (I hope you picked this one out on your own)
- newspaper (for putting under the pumpkin while carving)
- heavy paper (card stock)
- LEDs
- solder
- wire
- Arduino
- scotch tape
- 1 paper clip

Step 2: Build the LED frame

Picture of Build the LED frame
For this part, you should first print out a copy of the stencil at the same scale you will carve the pumpkin.

Next, Take a thick sheet of paper (I used 65 lb paper) and cut a shape out that will cover all of the openings in the cat pattern, but is not too close to the edge of the design (See a comparison in the second picture). Then cut a strip of thick paper about 5cm wide and attach it around the edge of the shape you just cut out.

When the edge is finished flip it over so you can see the inside.
The inside of the frame needs baffles to stop (most) of the light from bleeding between the sections. To achieve this, cut a slightly thinner strip of paper and tape or hot glue it to give definition around the tail, mouth and eyes as seen in the third and fourth pictures below.

To secure it to the pumpkin, take the paper clip (or a thumb tack) and a small strip of paper and attach them to the frame as seen in the last picture below. This allows the frame to stick to the pumpkin carving.

The final step is to coat anything that will touch the pumpkin in scotch tape, so it won't get soggy and tear half way through the night.