Sand Wheel
Eli's grandparents gave him a sand pit for his birthday (yesterday). I had a bit of time in advance to put together a toy to go in it. This is a classic type sand wheel, sand gets poured into the funnel at the top, drops out the hole onto the wheel making it turn. I'm quite surprised to discover that this assembled correctly first time. It was drawn as a combination of 3D modelling and converted to flat plans using Inkscape. Add in a dose of common sense and it all fitted together nicely and it actually works with sand in it. (svg here)
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