Category Archives: Quality


Feb06
Causes of Solder Empty and Tombstoning in Small Chip of Resistors and Capacitors

Recently, some people have asked about issues with solder empty in small chip SMD components like resistors and capacitors. Even after thoroughly checking the reflow oven profile settings and confirming everything is correct, solder empty still frequently occur with these … Continue reading

Jan24
Top ENIG PCB Issues: Black Pad and Phosphorus-Rich Layers Explained with Prevention Tips

With the rapid adoption of smartphones, the trend toward miniaturized electronic products, and the EU’s requirements for lead-free manufacturing, Electroless Nickel Immersion Gold (ENIG) surface treatment PCB has become a popular choice for many electronic products. This is largely due … Continue reading

Jan16
Inspection Methods for BGA Solder Ball Wettability and Soldering Defects

This is a summary post aimed at providing some guidance to newcomers in the electronics assembly field on methods for analyzing the solderability of BGA (Ball Grid Array) solder balls. Workingbear decided to write this after seeing someone ask about … Continue reading

Jan09
Why Do Electronic Component Leads Turn Yellow, Purple, or Blue After Reflow? Causes and Solutions

Workingbear recently received questions from readers about electronic component soldering leads turning yellow or showing discoloration (purple, blue, etc.) after going through the reflow oven. Why do the leads of components discolor after reflow? Does this discoloration affect product functionality? … Continue reading

Jan02
How to Monitor the Quality of Incoming Plastic Resin?

This is a answer to a question from a community member asking about plastic quality control. The question was: “Can we rely solely on MI (Melt Index) values to monitor the quality of plastic resins? And does an increase in … Continue reading