I wanted one of the copper light-up icosahedra for the bookshelf in my office. I wanted to be able to leave it on to enjoy periodically without putting a bunch of the CR2032 coin cells in the landfill. I also wanted it to be easy to operate without using tools, and not super fragile.

After a fair amount of experimentation, I came up with this tiny 3D-printed light. It uses a rechargeable LIR1254 coin cell that can be easily removed (or swapped) for recharging in an external charger.

The bottom panel hinges open for access to the light. I used strips of foil made for EM shielding applications and tiny neodymium magnets to hold it closed.

I have been playing with it for a few days, and it seems to meet my design brief above. It runs for at least several hours on a charge (I haven’t yet exhausted a fully-charged battery with it).

I put the 3D model (STL) for the battery holder in the Archive for free download, in case it is of use to anyone. There is also a basic icosahedron pattern with the previous Small Polyhedra post.

Copper rechargeable icosahedron with yellow light sits on a bookshelf with a ceramic Thor face jar and a pair of old pearl-and-brass opera glasses
Copper rechargeable icosahedron
Copper rechargeable icosahedron with the magnetically closeable panel open showing the tiny light inside
Copper rechargeable icosahedron with the magnetically closeable panel open showing the tiny light inside
Tiny 3D printed LED light built with an LIR1254 rechargeable battery and a Chibitronics Circuit Sticker
Tiny 3D printed LED light built with an LIR1254 rechargeable battery and a Chibitronics Circuit Sticker

There is a 3.5-minute video short walking through the design evolution and assembly.

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2 Comments

  3. I want one, the rechargeable light up, its mesmerizing. You have a lot of patience to work with something so tiny.

    Thank you for sharing your project.

    • Thank you! I wish I could make a bunch of these for other people, but they each take hours of attention. 😅

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