I have a product concept that now needs to move from sketches to something I can hold, test, and demonstrate. I’m looking for a mechanical designer / fabricator who can create production-ready STEP files and then build a single physical prototype that combines plastic and metal parts and operates exactly as intended. Here’s what I need from you: • Precise 3D CAD modeling and delivery of clean, fully-parametric STEP files ready for machining or printing. • Fabrication of a functional prototype that integrates the plastic and metal components, assembled and tuned so every moving part works smoothly. • Clear progress updates, photos or short clips during key build stages, and safe packaging for shipment when the unit is complete. The finish I’m after is a working model rather than a purely cosmetic showpiece, so tolerances and part interaction matter more than glossy surfaces. If you routinely turn designs into reliable prototypes and can manage both the CAD and shop work (3D printing, CNC, machining, or whatever mix you recommend), I’d like to hear how you would approach this, what lead-time you need, and any questions you have about the mechanism’s specifics. I’ll share drawings and dimensions under NDA so you can quote accurately and get started right away.