Selective Solder Vs Wave SolderIn PCB manufacturing, two main methods are used to attach electrical components to printed circuit boards - wave soldering and selective soldering. At Capital Equipment Exchange, we want to help you understand the different ways SMT machinery performs these processes to make the best decision when choosing equipment for your PCB assembly line.

Similarities In The Process

Both wave and selective equipment involve the same three main processes:

  1. Flux is applied to prepare the board, prevent oxidation, and alter the molten solder's surface tension.
  2. The printed circuit boards are preheated to avoid thermal damage to the board and components.
  3. Molten solder is applied to form joints and adhere components.

All About Wave Soldering

Wave soldering is a quick process. PCBs are moved over a molten "wave" of solder to adhere large quantities of leads at once. The flux, preheating, and application steps are combined into one convenient, reliable process.

  • Best For High Volume Production
  • Fewer Parameters To Change
  • Good For Larger PCBs

However, there are also limitations.

  • Smaller PCBs may require costly custom fixtures to be handled correctly by the machinery.
  • Irregular shapes can also be hard to handle and result in solder being placed incorrectly.
  • Double-sided boards are not ideal since components on the board's underside would be heat damaged.

Selective Soldering - What You Need To Know

For boards that are double-sided or jam-packed with components, selective soldering is often the more popular choice. That's because you can program these machines to "selectively" solder some components while protecting others from heat damage. The precision, accuracy, and reliability of your results will often depend on your programming.

  • Ideal For Double-sided Boards
  • Precise & Accurate
  • Strong Solder Joints
  • No Need For Flux Masking

Which Method Is Best?

While selective soldering can prevent faulty joint issues and save you in the long run on wasted solder, this process can take time to get just right. High SMT production lines that rely on a good mix of speed and reliability may benefit more from the wave process. The method with the highest accuracy - selective solder - is also the one with the longest production time.

We can help you weigh the pros and cons and choose the type of used SMT equipment that will best suit your business.

Purchase Used PCB Soldering Equipment & Save

Whether you choose wave, selective, or hand soldering, we look forward to helping you save time and money on the right used SMT equipment. Find reliable machinery from brands like Speedline Electrovert, Soltec, ERSA, and Sensby. At Capital Equipment Exchange, we also sell the parts to keep them going. We also carry SMT preheaters for your rework stations.

Contact us today to learn more or place your order.