Bicycle desk lamp

The desk bicycle desk lamp assembled

When my grandfather died I inherited an old bicycle headlight. The light was branded “starlight”. My plan was to hack it into a small battery driven mood light. However I never got to building the project… That was until this easter.

Easter hacking

I needed a small two day project for the easter holidays and chose to work on the idea. To make the light more useful I chose to go for a desk style lamp with a hinge like the Luxo Jr. from the Pixar movies.


To avoid thinking too much about the design, I designed it with focus on simplicity and most dimensions were based on the golden ratio. The base was made round like the light it self and dimensioned so that the diameter of the base was golden ratio * light diameter. The height was determined by the size of the electronics that I wanted to fit inside. As I had immediate access to a laser cutter I chose to go for a layer based design with multiple layers of plywood. To break the layers of wood I made one layer of black acrylic.

The lamp base After the parts were cut and the base assembled I sanded the walls to remove the burn marks.

The electronics

I had some small 4F 5V super capacitors that I bought from Aliexpress at some point, so I choose to integrate them into this build. This way the desk lamp could work without being connected. I added a USB micro female socket so that it could be powered and charged from a standard smart phone charger. The LED light bulb was rated for 12V, so I added a small step up circuit to step up the voltage from the 5 volts of the capacitors. Electronics within the lamp

Final assembly

On the image below you can see the final build. When charged it will light for 3.5 minutes without being connected. This is not much but enough for checking the clock at night. I may change the capacitors inside to some with a larger capacity at some point in the future.

The desk bicycle desk lamp assembled