Simple LED Butterfly Pin

This is the baby brother of my Neopixel Butterfly Brooch here on hackster and also on thingiverse. It's a pin you can attach to clothing with magnets, while it slowly fades in-and-out of a variety of colors to backlight the figure of a butterfly. It's a great way to get started Making, a fun project you can finish quickly.

The secret to this cheap and easy project is choosing the right components, just enough to do the job. It's very simple:

• 3D printed case designed to diffuse
• CR2032 Battery holder and switch
• Slow-fade RGB LED

For the interested: a longer form of this post is available on thisoldgeek.blogspot.com, detailing the "Maker's Journey".

Skill Level

Easy. 3D printing (about 2.5 hours total), solder 2-count 'em-2 joints, some hot glue and you're done! Maybe 30-45 minutes effort to prepare and assemble.

Cost: About $15 USD for components, not counting 3D materials.

Files: STL files available on thingiverse

Build It

• Print the 3D parts. Use white PLA for the insert piece with the butterfly, so it can glow. You can use white for the case if you want the whole case to glow, or another color for more contrast on the butterfly.
• Solder the LED flat against the battery holder on the side that says "Lilypad" in script - just two solder points, + for long LED leg, - for the short one. Bend/shape the LED so it covers all but the "L" in Lilypad - this positions the LED for best back-lighting on the butterfly. Test to make sure it works.
• Insert the battery holder into the mounts in the cover, aligning the left-over manufacturing tabs on the holder with the small mount recesses
• Make sure the tiny switch on the holder is aligned through the hole on the top of the cover
• Hot glue (or superglue, or your favorite adhesive) the battery holder to the inside of the cover. Don't use too much hot glue or the cover won't fit.
• Align the snap-on cover to the tabs/valleys on the case and slowly press down
• Attach magnets to the cover and the separate magnet holder bar with hot glue or other adhesive.