Main Content

A PID controlled DIY reflow hotplate using an Aluminium PCB to solder SMD components

Story :
Last time I made a reflow soldering hotplate from a regular clothing iron. And it works pretty great. The only issue is it uses mains AC voltage which I don’t feel super comfortable to work with so I tried low voltage DC approach.

The Idea :
The idea is simple, when you apply power to both ends of a conductor, it generates heat. So if we make a PCB that has a very lengthy trace and apply voltage to it’s end terminals it should generate enough heat to reflow a PCB. Key things to note here is that different solder paste has different melting point. and since my last experiment 200 to 220 degree celsius should be sufficient for the solder paste that I use.

Choosing PCB type :
So regular FR4 PCB is not a suitable option, But aluminium PCBs are made to withstand high temperatures and they spread the heat evenly throughout the entire surface. Although aluminium PCBs are bit more expensive, they are well suited for this job. So I started with designing the circuit.”

Link to article