The motion of Kristal’s Dragonfly model inspired me to build a functional LEGO version of the classic Piranha Plant from Super Mario Brothers. Although it shares some similar motion to the Dragonfly model, the mechanics are quite a bit different. Watch the video to see it in action and to learn how it works.
Although the mechanics ended up being fairly straight forward in the end, it took a lot of time and effort to get to that point. Often, the biggest challenge with models like these is getting everything to fit in the space required. I was determined to keep the pipe no larger than 10×10 studs in diameter, which meant I had to fit everything in an 8×8 interior space, minus the corners that make it ’round’.
In addition, I really wanted the crank to be on the back of the model. You may notice that on the demo model I show in the video, the crank is on the side of the model, which is the easiest and most logical place for it to go given the orientation of the chain drive. It actually took some significant rebuilding to fit all the gears needed to move the crank to the back, without interfering with the space required for rest of the mechanics when the plant was fully retracted.
In the end, it was time well spent, as I’m really happy with how it turned out.