PCB Repair and Rework

Printed circuit board (PCB) rework involves the modification, repair, or removal and replacement of electronic components to restore functionality or address design changes. This process demands a high level of precision, advanced tools, and skilled technicians, especially when dealing with complex multilayer boards and high-density component placements. At Accelerated Assemblies, we offer a wide range of complete PCB rework and repair services designed to address common and complex issues that can arise during the lifecycle of electronic assemblies. From ball grid array (BGA) packages to developing custom rework profiles for Surface Mount Technology (SMT) components, our team ensures every repair aligns with IPC standards and quality assurance practices.

• Lifted BGA Pad Repair: If pads lift from the board surface due to thermal or mechanical stress, we meticulously rebuild and reinforce them using high-quality adhesives and conductive materials.
• Ball Grid Array Reballing: We remove old solder balls and apply new ones using reballing stencils and solder spheres to restore functionality and ensure proper reattachment.
• BGA Solder Mask Repair: Damaged solder masks can lead to bridging or shorts; we use industry-approved techniques to repair or replace the mask without affecting nearby components.
• Component Replacement and Salvaging: Whether replacing a faulty BGA or salvaging a high-value component, our rework team ensures safe extraction and precise placement to minimize damage and maximize reuse.
• Design Changes in BGA Circuit Patterns: When a design revision requires internal routing modifications, we update BGA traces and pads using micro-jumpers or custom vias while maintaining signal integrity.

• Reflow of SMT Components: We perform targeted reflow operations to correct cold joints, misalignments, or non-wetted terminations using precision thermal profiling.
• SMT Rework Using Laser System: Laser systems allow for highly localized heating, enabling safe removal or replacement of components without exposing the entire board to thermal stress.
• Reapplication of Solder Paste Onto Substrate: In cases where solder joints are insufficient or missing, we reapply paste using screen printing or dispensing techniques to restore reliable connections.
• Rework Profile Development for Component Removal/Replacement: Each component type requires a unique thermal profile. We develop and validate custom profiles to ensure repeatable and damage-free removal and replacement.

• Surface Preparation: Before any repair work begins, we clean and prep the PCB to ensure optimal adhesion and conductivity for reworked areas.
• Mechanical Swaging and Eyelet Replacement: We replace damaged eyelets and use swaging tools to mechanically secure new ones, ensuring durable electrical and mechanical bonds.
• Removal and Reapplication of Solder Masks: For areas with damaged masks, we strip the faulty coating and reapply a new mask that matches the board’s specifications and solder resist characteristics.
• Adding Missing Mount Holes (for Populated Boards): When design changes necessitate new mount points, we add them without displacing existing components using precision drilling tools.
• Drilling Inner Ground Layers (for Populated Boards): When necessary, we drill into internal layers to add new connections or ground planes without affecting surrounding traces or vias.
• Stripping and Replacement of Contaminated Gold Finger Contacts: Worn or oxidized edge connectors are stripped and re-plated with high-quality gold to ensure proper mating and signal integrity.

• Cost Efficiency: Reworking defective PCBs is often more economical than discarding and replacing them. This approach minimizes material costs and reduces the need for new components, leading to significant savings. ​
• Enhanced Product Reliability: Correcting faults through rework ensures that PCBs operate as intended, decreasing the likelihood of future failures and increasing customer satisfaction. ​
• Improved Production Efficiency: Early detection and correction of errors streamline the manufacturing process, reducing downtime and accelerating time-to-market for electronic products. ​
• Environmental Sustainability: By repairing and reusing PCBs, manufacturers contribute to environmental conservation by reducing electronic waste and conserving resources and energy required for producing new boards. ​
• Adaptability to Design Changes: Rework allows for modifications to existing PCBs to accommodate design updates or feature enhancements without the need for complete redesigns, offering flexibility in product development. ​
• Quality Assurance: Implementing thorough rework processes ensures that only PCBs meeting stringent quality criteria proceed to the product, maintaining brand reputation and compliance with industry standards.

Restore your faulty PCBs quickly and reliably with Accelerated Assemblies’ expert rework services. From precision repairs to high-quality standards, we’ve got you covered. Reach out to our sales team today for a fast, customized quote that fits your needs.

FAQs

• How many times can a PCB be reworked before risking damage?
  The number of permissible rework cycles on a PCB depends on the cumulative thermal stress endured during processing. Industry standards generally suggest a maximum of three rework attempts for Class-2 and Class-3 boards, equating to approximately six heat cycles. These cycles include all soldering and reflow events, including original assembly on both sides.

• What is the technical difference between PCB rework and PCB repair?
  PCB rework involves modifying or replacing components on a board to meet original design specifications, typically due to defects or misalignment. It may also be done to add functionalities to the product as part of developing new versions. In contrast, repair focuses on restoring damaged circuitry or laminate structures that compromise board functionality, without necessarily restoring it to original design intent. Rework ensures compliance with IPC standards, while repair prioritizes functional recovery.

• Can a burnt PCB be effectively repaired?
  Yes, depending on severity, burnt PCBs can be partially restored by replacing delaminated copper traces and damaged substrates. Techniques may include micro-soldering, epoxy infill, and applying adhesive copper foil to reconstruct conductive paths. However, extensive thermal damage may compromise long-term reliability and require board replacement.

• What are the risks of excessive PCB rework cycles?
  Frequent rework increases exposure to thermal cycling, which degrades solder joints, delaminates PCB layers, and causes pad lifting. It can also deteriorate the laminate’s dielectric strength, leading to potential signal integrity issues. Adhering to rework limits is critical to maintaining board performance and reliability.