A key step in the manufacture of any electronic assembly is the mass soldering of the components to the substrate. The soldering can be conducted in one or more of several processes with convection reflow being the most widely used.

Selective soldering is replacing hand soldering, where a small number of through-hole components are fitted to an electronic sub-assembly. In the process, either the assembly is moved to the mini solder wave to make the joint, or the wave is moved to the assembly.