The squeegee assembly is a sub-system within a solder paste printer used to distribute solder paste across stencil apertures onto PCB pads. It comprises a blade holder, squeegee blades, and mounting mechanisms that work together to apply uniform pressure and create a consistent print. This assembly directly influences print quality, paste volume control, and stencil release in surface mount technology (SMT) manufacturing. The assembly is designed for use with polyurethane, stainless steel, and aluminum alloy components. Key parameters include blade material (SUS304 per ASTM A240), hardness (45–55 HRC per ASTM E18), thickness (0.15–0.25 mm), length (200–600 mm), angle (45–60°), operating pressure (1.0–1.6 MPa), print speed (10–150 mm/s), flatness (±0.02 mm per ISO 1101), edge radius (0.01–0.05 mm), operating temperature (15–35°C), and weight (1.5–3.0 kg). These values are reference ranges and must be verified for the specific model and application. The assembly is a component, not a standalone product, and its performance depends on integration with the printer. Buyers should confirm compatibility with their stencil and PCB dimensions, as well as the required print quality. Maintenance signals include blade wear, inconsistent paste deposition, or stencil damage. Failure boundaries include operating outside the specified temperature or pressure ranges, which can affect paste viscosity and print quality. Verification questions should address blade material certification, hardness testing, and flatness measurement. The assembly does not include the stencil or solder paste; those are separate items.
The assembly moves across the stencil with controlled downward pressure, forcing solder paste through stencil apertures onto PCB pads. Blade angle, pressure, and speed are regulated to ensure complete aperture filling while maintaining clean separation from the stencil. Dual-blade configurations use a front blade to flood paste and a rear blade to print. The blade material and hardness affect wear resistance and flexibility, while thickness and edge radius influence paste transfer. Operating pressure and speed must be set within the specified ranges to achieve consistent print quality. The flatness of the blade ensures uniform pressure distribution across the stencil.
