Final Inspection Checklist For Finished Boards Final inspection is the last opportunity to stop a defect before a board leaves the factory. It is not a search for perfection; it is a structured comparison between what the customer specified and what the panel actually contains, carried out against written criteria.…

Solder Paste Jetting: Practical Checks for Production Solder paste jetting deposits paste by firing a droplet from a valve rather than by squeezing it through an aperture in a stencil. The process removes the stencil, the squeegee and the board support from the equation, and it gives a non contact…

Packaging And Shipping Protection For PCB Shipments Packaging is the part of the process that protects everything the factory has just built. A board that passes every inspection can still arrive unusable if it was packed without regard for moisture, static or mechanical shock. The cost of the protection is…

Tooling Holes: Tooling Hole Placement For Panel Fixturing Tooling holes are the mechanical reference that ties a bare board or a panel to every machine that touches it. They locate the panel in the drill, the plater, the router, the stencil printer and the placement machine. If they are misplaced…

Drill Entry and Exit Quality in PCB Drilling Operations Every drilled hole has three zones that behave differently: the entry where the bit touches the copper, the barrel where the cutting happens, and the exit where the bit breaks through. The barrel gets most of the attention because it carries…

Solder Paste Life And Storage Requirements Solder paste is a perishable material. It is a suspension of fine metal powder in a flux vehicle, and both parts change with time and temperature. The powder oxidises slowly, the flux absorbs moisture from the air, and the solvent fraction evaporates. None of…

Solderability Testing Methods For PCB Finishes Solderability is the ability of a metallic surface to be wetted by molten solder under a defined set of conditions. On a bare board it depends on the final finish, on the amount of oxide that has grown since plating, and on contamination picked…

Lamination Cycle Parameters for Multilayer Boards Lamination is the step in which a stack of prepreg and copper becomes a single board, and the press cycle is the recipe that makes it happen. The resin has to flow far enough to fill the gaps around the inner layer patterns, cure…

Desmear Process Control in Multilayer Board Fabrication Desmear is the step that removes the resin left on the copper by drilling, and it is one of the few processes in a PCB shop whose failure is invisible until the board is electrically tested. A hole wall that has not been…

Rigid Flex Manufacturing Guide A rigid flex board combines rigid sections that carry the components with flexible sections that fold to connect them. The result replaces a cable and a pair of connectors with a single continuous circuit, which removes a set of contact interfaces and the failures that come…