Precision allmetal, startable coaxial Stirling Engine teaching model designed for handson exploration of thermodynamic principles and mechanical motion. Compact yet robust, this physical science experiment toy combines accurate machining and durable materials to demonstrate real Stirling Engine operation. Key features Coaxial design with a 20MM power cylinder and a 20MM 304 stainless steel heating pipe integrated in a single cylinder set for smooth, continuous operation. Diamondshaped transmission mechanism that meshes two sets of brass gears to produce synchronized, realistic motion that mirrors fullscale Stirling systems. Cylinder and piston machined from bearing steel GCR15 on a CNC lathe and hardened to 5862HRC to ensure precise fit and effective gas sealing during reciprocation. Oversized 78mm diameter flywheel weighing 155 grams to stabilize rotation and visually emphasize flywheel inertia and momentum. Brass gears and a brass crankshaft provide durable support for moving parts; total model weight approximately 1.4kg for a solid, educational feel. Allmetal construction and startable operation suitable for repeated demonstrations and study. Benefits and why you need it Teaches core physics concepts: thermodynamic cycles, heat transfer, pressure and volume relationships, and mechanical linkages in a tangible, visible way. precision materials and machining provide repeatable, reliable performance for classroom demonstrations or focused study. Compact but heavyfeeling construction makes the model easy to handle while providing realistic mechanical inertia and feedback. Startable design lets users observe the full cycle from heat input to mechanical output, aiding understanding through handson interaction. Practical applications Classroom demonstrations: Use during physics or engineering lessons to show Stirling cycle principles, heat engines, and mechanical synchronization. Lab experiments and student projects: Integrate into lab activities to measure rotational speed, observe sealing performance, and compare theoretical and realworld behavior. Hobbyist display and study: Suitable for collectors and model builders who want a precision, working example of Stirling technology for study or desktop demonstration. Specifications summary Power cylinder: 20MM Heating pipe: 20MM 304 stainless steel Cylinder and piston material: bearing steel GCR15, CNC machined, hardened to 5862HRC Flywheel: 78mm diameter, 155 grams Gears and crankshaft: brass Total model weight: approximately 1.4kg Construction: allmetal, startable, coaxial configuration The model delivers a clear, accurate representation of Stirling Engine mechanics with durable components and precision machining, making it a practical tool for education, experimentation, and mechanical demonstration.