I’ll go over the electronics/program in an upcoming post, but mechanically, my sound-reactive cigar box that I introduced a few weeks ago wasn’t too difficult to make. I’ll outline the assembly details in this post, starting with how I got the idea for such a crazy project.
The whole thing was inspired by someone giving me a cigar box, and then me thinking about how I could use it for a few months. After working on something quite different for Hackaday.com involving a LED strip and microphone, the idea for this device was hatched. I actually had all of the components I used in my garage, so that was definitely good budget-wise.
Part of what I wanted to do with the strip was to make the box virtually “look” left and right with the strip LEDs. This would be simpler than the ping-pong ball eyes that I physically rotated with the original “Boxie the creepster.” Additionally, I wouldn’t have to remote-control it myself.
Parts Needed for Project (Bill of Materials)
- Cigar Box – Places that sell cigars I suppose. Mine was a gift.
- Arduino Uno – Amazon, or see my review
- Standard Hobby Servo – Amazon, hobby store, Servocity
- Breadboard – Amazon, Adafruit, Sparkfun
- RGB LED strip – Adafruit
- 1 inch PVC pipe – Hardware store
- Microphone breakout – Adafruit, Sparkfun
- Hookup Wire – Adafruit, Amazon, leftover…
I used outdoor mounting tape like this this kind from Scotch Tape (Amazon) to attach the breadboard, Uno, and battery pack to the bottom of the box. This sticks well enough to keep everything secure, but things can be moved around if necessary. It’s also thick enough, and has enough “give” to account for the Uno’s solder points underneath.
To actuate the lid, I used the standard double-sided servo horn that came with the servo, and attached a 2.6 inch long piece of wood that came with the box to it to extend everything. The attachment was done by milling a 5/16th inch slot down the middle, sliding the horn in, and gluing.
When cut into another two pieces 1 1/4 inch long, this wood doubled as a servo mount, using a 6-32 hex bolt, and the super-glue tapping technique found here. The pieces of wood were lined up with the servo, marked, then drilled more or less by hand. The assembly was then super-glued to the bottom of the box to make a “lifter.”
LED strip “Eyes”
My original idea for this was to wrap the strip around the PVC pipe, but after trying this out, it seems too much bending tends to make the strips malfunction. After making this mistake, I milled a 3/16th inch slot into the side of the PVC pipe, and another 3/16th inch hole in the front to allow the light to go through in the middle. I then just threaded the strip through. This was also good because the box is kind of tight with the strip on the front, so putting it through the pipe saved a 1/4 inch or so.
The four hook-up wires from the LED strip go behind the “eyes” as shown and eventually snake onto the breadboard. I kinked them near the middle, which seemed to help everything bend when opening. There will be more information on this in the upcoming programming/electronics post.
Mechanically, building this wasn’t too hard, and I think the cigar box made a nice setting for this build. There were a few tricks to programming it correctly, so be sure to check back and see how this was done. Also, check out the intro post for video of this box-thing in action.