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…

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: Teaching the Team 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…

PCB Desmear Records: Writing It Down 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…

PCB Desmear Audit: Checking the Practice 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 auditing desmear…

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…

Conveyor Rollers on an Etch Line: 4 Checks for Even Tracking Conveyor rollers are the part of an etch line that carries the panel through the chemistry at a controlled rate. Their condition decides whether the panel arrives at the exit when the process expects it, and whether it arrives…

Permanganate Sludge Control: 4 Checks for a Clean Desmear Line Permanganate sludge is the solid material that forms as a permanganate desmear bath does its work. It is a normal product of the reaction rather than a fault, and managing it is one of the duties that decides whether the…