This Stirling engine is a precision desktop demonstration unit that converts heat into smooth mechanical motion. Machined by CNC from materials, it combines sturdy construction with a refined appearance for education, display, and handson exploration of thermodynamic principles. Key benefits Clear demonstration of heat to motion conversion: air cooled design and a visible flywheel make the Stirling cycle easy to observe and explain. Durable, precision construction: critical components are CNC machined from 6061 aluminum alloy, brass, 304 stainless steel, and SUJ2 bearing steel to provide consistent fit and motion. Low maintenance and clean operation: surface treated parts are oil ; anodized aluminum parts preserve finish and appearance. Quiet, engaging operation: the engine runs with a low audible signature, making it suitable for classrooms, desks, or meeting rooms. Materials and construction highlights Main body, bracket, flywheel, and fan made from 6061 aluminum alloy. Power piston made of brass. Heating tube made of 304 stainless steel, inner diameter 20 mm. Power cylinder made of SUJ alloy steel. Ventilation piston and other precision parts from 6061 aluminum alloy. Bearings and shafts from SUJ2 bearing steel. All parts processed by CNC machining and finished with surface treatment and anodizing. Dimensions and weight Overall size: 105 x 105 x 218 mm. Flywheel diameter: 65 mm. Fan diameter: 102 mm. Piston stroke: 16 mm. Piston diameter: 16 mm. Net weight (aluminum alloy parts): 970 g. Total weight with packaging: 1100 g. Operation Place the engine in a cup of boiling water and wait about 20 seconds. Turn the flywheel gently to start motion. Once started, the engine runs quietly and slowly for approximately 20 to 30 minutes as it converts the heat input into mechanical rotation. During operation the power piston produces a faint sound, quieter than a clock tick. Design and appearance Hollow decorative cutouts in the structure form a flowerlike pattern for an attractive visual effect while running. Four aluminum feet and four goldcolored fasteners on the panel add contrast and stability. Anodized finish improves surface hardness and provides a lasting metallic sheen. Practical use scenarios Classroom demonstration: Use as a handson explanation of thermodynamic cycles, heat transfer, and basic mechanical motion in physics and engineering lessons. Office desk display: A quiet kinetic desk piece that provides visual interest and a calm distraction during breaks. Hobbyist demonstration and collection: Suitable for collectors and model engineers who appreciate precision machining and visible mechanical motion. What is included and compatibility Fully assembled Stirling engine ready to operate with a standard cup of hot or boiling water. No special fuels or external power sources required; works with a simple hot water heat source. This unit is a compact, precisionmade Stirling engine that balances durable materials, accurate machining, and an appealing aesthetic for educational, decorative, and hobby uses.