HEPA Fume Extractor

THE AERODYNAMIC PROBLEM Most cheap desktop fume extractors are effectively useless. They rely on standard axial fans (like PC case fans), which are designed to move a high *volume* of air through free space. However, the moment you introduce thick, dense filtration media like a True-HEPA filter and a bed of activated carbon pellets, the airflow resistance spikes. Axial fans lack the static pressure to overcome this resistance, causing the air to stall and the extractor to fail. THE CENTRIFUGAL SOLUTION To solve this, I threw out the axial fan design entirely and engineered a custom high-static-pressure centrifugal blower from scratch. - The "Snail Shell" Housing: Modeled a custom volute (snail-shell) casing. This geometric expansion zone allows high-velocity air coming off the impeller blades to efficiently convert into high-pressure air. - Custom Impeller: Designed a precisely toleranced radial impeller to maximize air intake and maintain extreme pressure without stalling the motor. - Heavy-Duty Filtration: Integrated a perfectly sealed dual-chamber system. The sheer volume of the HEPA filter and the bed of raw activated carbon pellets guarantees that toxic flux fumes and VOCs are fully neutralized. - Precision Control & Capture: The unit features a multi-directional articulating hose to pinpoint the extraction zone directly at the soldering iron, ensuring zero fume escape. FABRICATION & ASSEMBLY The entire system, including the internal aerodynamics and the external chassis, was modeled in CAD and manufactured via 3D printing. Getting the tolerances between the spinning impeller and the static volute wall tight enough to prevent pressure leaks required several iterative prototyping phases. The final result is a formidable, variable-suction extraction unit built entirely from scratch.