Issue link: https://iconnect007.uberflip.com/i/1546025
46 SMT007 MAGAZINE I AUGUST 2026 shielding, nozzle selection, or airflow settings may cause adjacent solder joints to reflow or small components to shift. Custom nozzle requirements: Hot air rework often requires a nozzle sized closely to the target compo- nent. Unusual package dimensions or crowded layouts may require custom tooling, increasing setup time, cost, and lead time before rework can begin. Localized thermal stress: Concentrated top- side heating can create a temperature difference between the component area and the rest of the PCB, particularly when bottom-side preheat is insuf- ficient. Excessive ramp rates or uneven heating can increase the risk of PCB warpage, package warpage, delamination, or damage to the rework site. Cons: Infrared Affected by surface properties: Infrared heating is influenced by the color, emissivity, reflectivity, and finish of the component and PCB surfaces. Dark or matte materials may absorb energy quickly, while shiny metal lids, exposed copper, or light-colored surfaces may reflect energy and heat more slowly, making temperature control less predictable. Less localized heat control: Infrared systems typi- cally heat a broader area than a fitted hot air nozzle. This can expose nearby components, connectors, and the PCB laminate to additional heat, particularly when the rework site is densely populated or close to temperature-sensitive materials. Line-of-sight heating limitations: Infrared energy primarily heats surfaces directly exposed to the emitter, while raised components, shields, and surrounding features can block or redirect the energy. This may create uneven heating or require additional shielding and thermal profiling to ensure K N O C K I N G D OW N T H E B O N E P I L E K N O C K I N G D OW N T H E B O N E P I L E Figure 2: PCB and component surface properties influence infrared heating: Dark, matte materials generally absorb radiant energy more readily, while shiny metallic surfaces reflect more energy and may heat more slowly.