Selective soldering or wave soldering: which process fits?

What distinguishes the processes?

In selective soldering, flux is first applied locally. After preheating, a small solder wave processes the programmed locations. Travel path and contact time can be adjusted for each joint. In wave soldering, the assembly passes over a continuous solder wave after flux application and preheating. All relevant THT joints must be accessible to the wave.

The assembly decides

First check the full PCB format, including production panel or carrier. Then assess spacing between THT and SMD components, solder access, component heights, copper areas and heat sensitivity. Dense layouts may require local processing; other assemblies suit a continuous wave process. Production volume alone is not a reliable basis for a general decision.

Cycle time and manufacturing integration

Comparison must include total process time and material flow. The number and position of joints affect travel paths in selective soldering. In wave soldering, conveyor, preheating length and a suitable solder-wave configuration matter. Both processes can be integrated into a production line; the exact configuration depends on the model.

Samples and quality criteria

A soldering trial with actual assemblies provides a sounder basis for the decision. Document flux, solder, layout, required joint quality, keep-out areas and relevant component limits. Compare results against criteria set beforehand, rather than machine specifications alone.

Frequently asked questions