Managing Component Scrappage Rates in Customer Supplied Assembly Kits
Provide clear overage buffers and factory reels to prevent line starvation, setup material waste, and downtime charges during surface-mount assembly.
First Article Inspection Scrap
Production Waste
Destructive testing and machine calibration often require the use of actual components and boards to verify a new process setup. The resulting first article inspection scrap includes any assemblies that are sacrificed during initial thermal profiling or cross-sectional analysis to confirm quality standards. This material is intentionally consumed to ensure that the rest of the production run meets the design requirements.
Verification Cost
Engineers use the first few boards from a new lot to calibrate solder paste inspection and automated optical inspection systems. During this phase, first article inspection scrap might be generated if a board is run through a reflow oven with thermocouples glued to critical points. These boards are typically marked as non-salvageable because the adhesive or the thermal stress of multiple passes exceeds the allowable limit for a customer shipment.
Process Boundary
While this waste is planned, excessive losses during the initial setup can indicate a lack of process stability or poor programming. Controlling the amount of first article inspection scrap is a primary goal for high-mix low-volume manufacturers who must frequently change setups. If the inspection reveals a fundamental design flaw, the scrap serves as a final check that prevents a much larger loss of the entire batch.
This material loss is a necessary investment in the integrity of the subsequent assembly volume.