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.
Paper Tape Fiber Shedding
Contamination Risk
Loose particles originate from the edges or surface of adhesive tapes used to secure electronic components during automated placement. Paper tape fiber shedding occurs when the carrier material degrades under mechanical stress from feeding sprockets or vacuum nozzles. These microscopic cellulose fragments deposit onto the solder mask or copper pads before the reflow process begins.
Such debris creates physical obstructions that prevent proper wetting during soldering. Contamination of this nature frequently causes electrical shorts or localized voids in the solder joint.
Material Mechanism
Abrasion against the drive mechanism of a pick and place machine breaks down the structural integrity of the paper carrier. Higher feed rates accelerate the separation of fibers from the base material. Heat within the feeder area dries the paper and reduces its resistance to mechanical wear.
Once airborne or loose, particles migrate toward the suction cups or the exposed component leads. Gravity and electrostatic attraction pull the shed fibers into the assembly field where they trap under the body of a surface mount device.
Process Consequence
Excess particles lead to inconsistent impedance or thermal failure in miniature surface mount packages. Quality control teams detect these faults through automated optical inspection or x-ray analysis after the soldering cycle. Replacing paper tape with plastic carriers removes the source of cellulose debris from the production environment.
Machine settings that lower the tension on the feeder assembly reduce the rate of material breakdown during operation. Maintaining clean feeders and ensuring proper alignment of the tape path prevents the mechanical binding that initiates the degradation of the carrier strip. Proper handling of input materials remains the primary method for ensuring the integrity of the finished circuit assembly.