Creep Corrosion Control on PCB Assemblies: 6 Rules Creep corrosion is the migration of corrosion products across a surface, away from the metal that produced them. It is not the same as ordinary corrosion, where the damage stays close to the affected area. In creep corrosion the product spreads as…

Rosin Flux Chemistry Control in Wave Soldering: 6 Rules Rosin is a natural resin obtained from pine, and in a soldering flux it does two jobs at once. It forms a protective film that keeps oxygen away from the hot metal, and it provides the vehicle that carries the activator…

Mesh Count Selection for Solder Paste Printing: 5 Rules Mesh count is the number of threads per inch in a printing screen, and it is one of the quiet variables in a solder paste printing process. It decides how much paste passes through the screen, how much is held back,…

PCB Desmear Standards: Agreeing the Rules Modern electronics depend on boards that are assembled correctly the first time. Every product – a phone, a charger, a medical instrument or an industrial controller – relies on thousands of solder joints that must conduct current for years. This article explains PCB desmear…

Tack Free Time Control for Conformal Coating: 5 Rules Tack free is the point at which a coating has dried enough that dust no longer sticks to it and a board can be touched without leaving a mark. It is not the point of full cure. A material can be…

Halide Content Control in Soldering Flux: 6 Rules The active part of most fluxes is a halide salt or an organic acid, and the halide is the more aggressive of the two. Chloride and bromide ions attack the oxide on the copper surface, convert it into a soluble salt and…

PCB Desmear Training: From Design to Repeatable Production Modern electronics depend on boards that are assembled correctly the first time. Every product – a phone, a charger, a medical instrument or an industrial controller – relies on thousands of solder joints that must conduct current for years. This article explains…

PCB Desmear Records: What Buyers and Engineers Should Check Modern electronics depend on boards that are assembled correctly the first time. Every product – a phone, a charger, a medical instrument or an industrial controller – relies on thousands of solder joints that must conduct current for years. This article…

PCB Desmear Audit: Design, Process, and Quality Notes Electronics manufacturing has become a discipline of small details. Solder paste volumes, placement accuracy, temperature profiles and inspection limits all add up to the final result. This guide looks at PCB desmear audit from the perspective of a PCBA factory floor, covering…

Develop Breakpoint Control in Solder Mask Development After the solder mask is exposed, the unexposed resist has to be washed out of the openings, and the point at which that removal is just complete is the develop breakpoint. Run the panel a little past that point and fine features lose…