While growing up in the 80s, I occasionally envied the cool, skater punk kids in their military surplus jackets, covered in safety-pins and angst-ridden, handmade patches. Now that I have reached an age where I'm expected to focus on the practical things in life, I've been itching to combine my love for wearable tech with a little nostalgia. Plus, a college student recently told me that DIY patches were sort of a "thing" again, which got me wondering. Could I create a TARDIS patch and then light it up, Doctor Who style?

In this Instructable, I will show you a method for making your own light-up TARDIS patch jacket, by re-programming a LilyTiny or LilyTwinkle microcontroller (or other Arduino-based microcontroller), and adding in a few Adafruit NeoPixels. To see the jacket in action, you might want to view the video at the top.

In the process of creating an inspiring wearable, you might even rekindle your youth.

Step 1: Find an Old Jacket

First, find a suitable over-shirt or jacket. I found this gem at a second-hand store for $10.

Step 2: Gather Your Tools & Supplies

Once you have a jacket, it's time to gather your tools and supplies.

SUPPLIES

1 X LilyTiny or LilyTwinkle

1 X LilyPad Tri-color LED

4 X Adafruit NeoPixels

Smooth Conductive Thread

Light-colored Fabric

Battery Holder

2 X Coin Cell Batteries

Switched JST Breakout Board

5mm Sewable Metal Snaps

1 X TinyAVR Programmer

IC Test Clip SOIC 8-Pin

Blue Fabric Paint

Paintbrush

Sharp Scissors

Needle

1 sheet of Sticky Label Paper

Jumper Wires

Stranded Wire (optional)

Heat' n Bond Iron-on Adhesive (optional)

TOOLS

Cricut Machine (or a similar gadget)

Weeding Tool (optional, but useful)

Clear Nail Polish

Glue Gun

Sewing Machine (optional, but useful)

Alligator Clips (good for prototyping, if you have them)

Soldering Iron

Step 3: Make Your Patch

Find a Tardis SVG file that you like.

I cut mine out of sticky-backed label paper using a Cricut Air Express 2. If you don't have a similar tool at your disposal, you can cut out a design using a pen-knife.

After removing the backing from the sticky-backed paper, I placed the negative image of the design onto a piece of white fabric. I pressed the sticky-backed paper down well, so there weren't any air bubbles on the edges. Then I applied three coats of blue fabric paint to it, allowing each layer to dry before applying the next one.

After the paint was completely dry I carefully removed all of the paper, using a weeding tool.

When I removed the paper, my doors didn’t look quite right. Because the boxes on the door panels were all white, I went in and painted them blue, leaving only a white frame around the panels.

After giving the paint a day to cure, I washed the patch, let it air dry flat, and ironed it.

Optional: You might consider ironing some Heat n Bond iron-on adhesive to the back of your fabric, if it's too flimsy.

Step 4: Program Your LilyTiny/ LilyTwinkle

Use a TinyAVR Programmer, jumper wires, and an IC Test Clip to re-program your LilyTiny/ LilyTwinkle using the Arduino IDE.

If you aren’t sure how to do this, check out SparkFun’s Guide for Re-Programming the LilyTiny/ LilyTwinkle.

Alternatively, you could use another Arduino-based microcontroller of your choice, such as a Gemma, Flora, or LilyPad. I chose the LilyTiny for its size and affordability.

You can find the code for LilyTiny_Tardis.ino on my Wearable Electronics repository on Github.

You may need to change the pins in the code if you're using a different microcontroller.

Step 5: Follow the Circuit Diagram to Sew Circuit

Use the circuit diagram to set up your components. Pay particular attention to the way you position the NeoPixels, to make your sewing easier.

I placed my patch over the components to assist with their placement.

I had to make a couple of insulating bridges, since a couple pieces of my conductive thread needed to overlap in places. I used extra pieces of fabric to insulate the threads, but you might have another method.

I used a dab of hot glue on each sewable component to keep them in place while I sewed. Just be careful not to get glue on the conductive pads.

Note that there are 5mm sewable snaps on the back side of the fabric (see circuit diagram) that will attach to the JST Breakout Board and battery pack.

When sewing with conductive thread, it's important to secure your knots with clear nail polish to keep them secure.

Step 6: Prep JST Breakout Board

I decided that I wanted to be able to access my battery from the inside of the jacket, so I sewed snaps to the opposite (back) side of the fabric. This makes it easy for me to remove the JST Breakout Board and battery pack when I need to wash the jacket.

In one iteration, I soldered wires from the JST Breakout Board to female snaps, to match the male snaps I'd already sewn into my circuit.

In another iteration, I soldered jumper wires directly to the snaps, and then slipped the female ends of the jumpers to header pins soldered to the JST Breakout Board. It doesn't matter how you approach this, as long as the snaps connected to the JST Breakout Board connect with the ones you've already sewn down.

I used a bit of Velcro to secure the battery pack.

Step 7: Test Your Circuit

Using alligator clips and a battery pack, I tested my circuit to ensure that everything was working, before I ironed and sewed the patch to my jacket.

NOTE: Be sure to use fresh batteries. In this Instructable, I used two coin cell batteries. If you have access to a lithium polymer battery (and you are confident with your sewing skills), you could use that type of battery instead. Just be careful not to damage or puncture it.

Step 8: Iron & Sew Down the Patch & Insulate the Circuit

Once you know that your circuit works, iron the patch to your jacket, carefully lining up the sewn components with the windows in your TARDIS.

I used a zig-zag stitch on my sewing machine to attach the patch. Be careful near the top of your TARDIS, so that your sewing machine doesn't come in contact with the Tri-color LED at the top.

After sewing on the patch, I used a little hot glue to insulate the traces and knots on the inside of the jacket.