Grounding SMT Setup Delays and Attrition Limits in Assembly Agreements
Assembly agreements define line setup boundaries and package specific attrition limits to prevent unexpected downtime surcharges and inventory deficits.
Cut Tape Component Loss
Tape Handling Waste
Manual loading of short tape segments into surface mount feeders results in a specific volume of discarded parts. This cut tape component loss occurs because pick and place machines require a leader length to thread the carrier through the feeder mechanism. Short strips of components lack the standard leader found on full reels.
Production Impact
Small batch assembly frequently accounts for cut tape component loss by ordering parts in excess of the bill of materials requirements. Machine operators cannot access the first few components because the cover tape must be peeled back to reach the drive sprockets. This physical constraint forces the sacrifice of several units per strip.
Automation requires a minimum tape length of approximately 10 to 15 centimeters to engage the take-up wheels successfully. Without this length, the machine cannot maintain the tension needed for consistent component indexing.
Economic Mitigation
Assembly facilities may splice a leader onto the strip to reduce cut tape component loss during high mix production. While this process adds labor time, the method saves expensive integrated circuits or sensors. The choice between splicing and absorbing the waste depends on the unit cost of the part relative to the assembly labor rate.