Rubber-band powered paddle boat with Lego seat

thingiverse

This was one of my son's first 3D printing projects some years ago, when he was 7 years old. His school has a 3D printer, but only for printing things that students design themselves. His teacher recommended TinkerCad to start, and I coached him a bit, but this is overall his own work except for the Lego brick in the middle, which I helped him import into TInkerCad. We didn't have a 3D printer back then. The the result pictured is what his teacher printed using ABS (same as Lego) but any material can be used. This object was made in Tinkercad. Edit it online https://www.tinkercad.com/things/3QtEklpQOVT Operation --------- Find a thin rubber band, tie it off so you can loop it gently around the two booms, and thread the paddle wheel through the rubber bands. Turn the paddle blades to wind it up. Optionally stick a Lego person on the seat, put the boat in calm water, and let go of the paddle wheel. Improvements ----------- If we were to do this again, we'd widen the boat so that a standard rubber band could be used without tying and cutting it. This would also give the rubber band more room to wind up on either side of the paddle wheel. We might also raise the boat transom or cover the back end to prevent the paddles from splashing water into the boat. Otherwise, it works reasonably well.