It took me a while to figure out the right term for these shells. They are limpets and not barnacles, as i originally thought they were >>
I've always liked collecting seashells, and have always wanted to do something more with them than accumulate them in my parent's garden. So now I want to see how far I can go to integrate small electronic circuits inside them. Limpets are nice to work with because they are totally open on one side and the bigger ones even offer some depth.
The limpet buttons are very simple, they use a push-button to trigger LED light or a vibration motor. I decided to use a push-button rather than a switch so that they are only active when touched/pushed.
Step 1: Materials and Tools
- Limpets from the beach
- Push-button switch
- LED or vibration motor
- 3V button battery holder
- 3V button battery
- Hot glue
- Soldering iron
- Hot glue gun
Step 2: Preparing Components
First you will want to make sure you have found the smallest components possible and that when assembled they all fit inside the limpet you would like to use.
If things don't quite fit, you can try sanding down the button battery holder around the edges, finding an even smaller push-button and a smaller LED and/or vibration motor.
Superglue the push-button to the side of your button battery holder, so that the pushy part sticks out just slightly over the rim of the limpet.
Step 3: Circuit
Solder one of the push-button legs to the closest battery holder leg.
Place the LED or vibration motor on the bottom of the button battery holder. Keep in place with some sticky tape or hot glue if necessary. Solder the connections, make sure to solder the positive leg of the LED to the positive leg of the battery holder.
See schematic and illustration for details >>
Step 4: Hot Glue
One last time, place the limpet on top of your circuitry and check if it works.
Fill the limpet with some hot glue, less than half full. Then insert the circuitry and push down so that it is in the right positions. turn upside down and check to make sure it will work. then let it cool.