Head Lamp

cults3d

I required a headlamp for a location where light does not exist. It's an area devoid of people and other sources of illumination, making it extremely dark at night. Additionally, there are no stores in the vicinity where you can purchase batteries. Fortunately, power is available. I created this headlamp that can be charged using a phone charger. The Li-ion battery charger PCB costs me only 1.5 euros. I sourced a 4.2-volt battery from a low-cost Bluetooth speaker. The dimensions of this battery are 34.5x37x5.5mm, but its capacity remains unknown. To prevent water ingress, I used PET-G to make the headlamp watertight. As a result, the power button is located outside the case; otherwise, rainwater would find an additional entry point. The LED is a high-power 3W unit connected in series with a 1 Ohm resistor. This LED is thermally bonded to a plate of aluminum (46mm x 1mm) to keep it cool. The "glass" is cut from a 2mm acrylic sheet (52.9mm). I obtained the elastic band (24mm x 1.25mm) from a tailor shop, although sewing isn't my forte, as you can see. The headplate comes in two different sizes, and the photo shows the smaller one. The lamp is adjustable using an M3x20mm screw (you'll also need an M3 nut). I routed the wire from the switch to the lamp instead of directly inside the case to prevent water from reaching the battery. Li-ion batteries are extremely sensitive to water and can react explosively when exposed to it.