Simple Color Changing LED Hat

This is a pretty quick project for making a color changing LED Hat. I used Slow-Flash LEDs but you can also get Fast-Flash.

This creates some basic animation without using a wearable microprocessor. I'll tackle that in my next Instructable.

I used -

• 2 Diffused 5mm Slow Fade Flashing RGB LEDs
  
  • https://www.adafruit.com/products/679#tutorials
• Conductive Thread
  
  • https://learn.adafruit.com/conductive-thread/over...
• Sewable coin battery holder with switch
  
  • https://www.kitronik.co.uk/2711-electro-fashion-s...

a baseball cap with small grommet-ed holes in the top

a coin cell battery (CR-2032)

tools - sharp scissors, small jewelry pliers (both flat and rounded)

For this hat, stick each LED into one of the two front holes of a baseball hat with grommet vents (little holes). Then bend them as follows

The longer lead of the LED is the positive side and is called the anode, and the negative one is called the cathode. To keep them straight, I bend the anode into a small square and bend the cathode into a circle.So you have a square loop and a circular loop on each LED- inside the top of the hat.

Depending on the weight of the conductive thread, you might not need a needle to do this project. Using the thread connect the positive sides of the LEDs to the positive sides of the battery holder, aiming to keep the battery holder centered on the top hat seam.. Wrap the thread tightly and several times around each connection (ie. the LED ‘loops’). Make sure it works - if the LEDs flicker, the thread is not consistently holding on to the connection. Also make sure that you keep the thread ends out of the way while testing.

Also make sure the thread is not so tight that you can’t wear the hat.

Once it works, you can cut the loose ends and use clear nail polish to secure the knots/tie offs. You can secure the battery holder for a quick fix with black electrical tape - or you can make a more elaborate fabric cover. Just keep in mind that you should be able to access the switch (if you used a battery holder with one) and have access to change the battery.