Self-Soldering Circuits

Challenge: Make a circuit reflow-solder itself & other circuits!

Here's the simple idea: embed a small resistor in the form of a track within one layer of a printed circuit board. Apply a voltage to heat up the resistor, melt the solder on the surface, and solder the components. But there's more – if the circuit is a soldering temperature controller, you can use it to reflow other circuits using the same technique. It's like RepRap for soldering!

PCB Heaters

Challenge: Make the circuit board generate its own heat

You've probably seen 3D printed heatbeds, typically made from printed circuit boards with a track that heats up like a resistor. But what are the limitations, and can it be used as a soldering hot-plate?

Well, it does work, but even with low-temperature solder-paste (165°C), it exceeds the safety limits of the PCB.

Other materials, like Polyimide Flexible PCBs (with a maximum of 100°C) will deform and discolor over time. The only PCB material that can handle the heat is ceramic. However, the cost makes it impractical.

So for applications exceeding 100°C, we recommend using it only for one-time use, like the Self-Soldering example.