Electrostatic Discharge Control in PCB Production Electrostatic discharge is a small event with a large consequence, and it is invisible in the two ways that matter. The discharge itself cannot be seen, and the damage it causes often cannot be seen either, because a component weakened by static may pass…

PCB Trace Corner Design And Acid Traps Every change of direction in a trace is a small discontinuity. At low speed and at moderate current a right angle corner makes no measurable difference, and the practice of rounding corners is often justified by tradition rather than by analysis. At high…

Cleanroom Requirements for PCB Manufacturing Not every step of board manufacture needs a cleanroom, and the mistake most shops make is either to build one where it is unnecessary or to run a sensitive process in an open area. Particle contamination matters most where a small defect is reproduced many…

Environmental Compliance in PCB Manufacturing Environmental compliance in a board shop is a set of measurable obligations attached to a permit: what may be discharged, at what concentration, in what volume, with what monitoring and with what records. It is also a business risk, because a suspension of a discharge…

Chemical Handling Safety in PCB Manufacturing A board shop handles acids, alkalis, oxidisers, solvents and metal salts, and the risks are managed through a small number of practices that are easy to describe and easy to neglect. Chemical handling safety is not primarily a matter of rules and signs. It…

Drill Hit Count Control In PCB Fabrication A drill bit in a printed circuit board shop does not drill one hole and stop. It drills a set number of holes, is withdrawn, and is replaced or resharpened. That number is the hit count, and it is one of the most…

Waste Treatment and Recycling in PCB Manufacturing Waste treatment is often treated as the cost of staying legal, and in a board shop it is also a cost of production that can be managed. The chemicals that leave the plant in a waste stream are chemicals that were bought, handled…

Via Plugging With Ink Versus Conductive Paste When a via has to be closed, two materials are used: a non conductive solder mask ink, and a conductive paste filled with metal or carbon. Both fill the barrel, and they behave very differently in the finished board. The choice is normally…

Component Placement Force And Z Axis Control The placement machine presses each component onto its paste deposit with a controlled force, and that force is one of the least discussed and most influential settings in the assembly process. Too little force and the part sits on top of the deposit…

Solder Paste Metal Loading And Print Quality Solder paste is a suspension of metal powder in a flux vehicle, and the metal loading is the fraction of its mass that is metal. A typical paste is between eighty five and ninety percent metal by weight, which corresponds to roughly half…