It all started with an observation at the lake: a colleague watched kids playing with a small, electric paddle-wheel boat. That triggered the idea: this has to work on land too (but completely without electronics, using nothing but the pure power of water). However, the reality of prototyping was a tough battle against physics. The first designs were way too heavy, scaling at over 350 grams 🙈. In a pressureless system, every single gram counts. If the cehicle is too heavy, the momentum of the water jet simply isn't enough to accelerate the mass. We didn't give up. Instead, we put the model on a radical diet. We dove deep into the mechanics of water turbines, optimized the water wheel blade by blade, and ran countless test prints with varying wall thicknesses, nozzle diameters, wheel sizes, clearances and infill settings. The first versions were also unfortunately way too large, so we went through further optimization to ensure the HydroMover fits perfectly on smaller print beds, as many families have an A1 Mini printer at home. The result of this optimization: the final model weighs just under 180 grams. In the photo, you can see the bulky prototype on the left and the final on the right. You can easily imagine how much material and print time this evolution saved. 😅 ​ At the same time, the goal was to create a real STEM kit for kids. This meant: robust components that are easy to grip, and as few individual parts as possible. No fragile clips that snap off, no tools, no glue. Just 11 parts that fit together perfectly. ​ The hard work paid off. The final Version of our HydroMover runs smoothly, saves material, and shows kids firsthand how mechanics and physics actually work. We hope you have as much fun printing and testing it as we had developing it! #ChildrensToys #Contests #toy #Newmodel #Weekly Roundup #Sharing Makes #kindertag #Kids #Toys #HydroMover #Summer #playtime #Stem #Physics #Easyprint #Outdoors(Edited)