Wave Soldering Defects


Lifted Resist on a Printed Circuit Board

Figure 1 shows a very obvious example of resist lifting from the surface of the board after soldering. Quite simply this is due to incorrect specification of the printed board. Tin/lead should not be used under resist on professional circuit boards. As the tin/lead moves into a liquid phase it expands and may cause loss of adhesion between the solder and the resist. If the resist is brittle or thin it will separate as shown in Figure 1. It is possible to use tin/lead if the thickness of the coating is less than 3-5µm as there will be very little movement during wave or reflow soldering.



Figure 1: The resist lifting here is due to incorrect specification of the PCB
Figure 1: The resist lifting here is due to incorrect specification of the PCB.

Celebrating 70 Years of Manufacturing Excellence
America's Oldest. A History of Innovation.

Over the past 70 years, the electronics manufacturing industry has changed dramatically as the industry continues to adapt to evolving demands and technology. Epec is at the forefront of innovation, with the expertise and agility to move at the speed of today’s businesses. At Epec, the customer comes first, and everything we do must be put through that filter. Whether it is developing e-commerce platforms to make it easier to work with us or creating a new product introduction (NPI) process that helps our customers get to market faster, we must focus on building the new. By doing that every day, and by always making the customer our top priority, we plan on being here for another 70 years and then some.

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Celebrating 70 Years - Epec Engineered Technologies