This is a soldering badge kit that I designed for Valorworks, a maker group getting started at Valor Collegiate Academy. The design is based on their school's logo. Costs came out at $2.05 per board (qty 50).
Altium CircuitMaker was used to design the schematic & PCB. The files are open source and available here. The design uses four flashing 3mm orange LEDs on the points of the compass and a single 0603 SMT blue LED in the center. They're all powered by a single 3V CR1225 coin cell battery.
The design works well with one exception. The battery voltage drops off quicker than I'd expected and as a result it falls below the 2.8V forward voltage of the blue LED within 10 minutes and it stops functioning. The orange LEDs continue to function for another 48 hrs. We're using the cheapest batteries that can be found on eBay. So, these numbers can likely be greatly improved by simply using a higher quality battery. For this batch, it was decided to eliminate the blue LED and its resistor. If a second batch is needed in the future then we'll consider a hardware revision.
Assembly instructions are in the video below. Note that the steps to solder the blue LED and SMT resistor are not needed in the v1.0 badge.
If you or your company are interested in having a custom soldering kit created for a workshop, birthday party or other event contact me with details.