Given some biodegradable 3D printing filament and tasked with doing something creative with it, Vimal Patel built an extruder using Lego, attached it to a rather ordinary hot glue gun and ended up with a pretty funky 3D printing pen – a DIY 3Doodler if you will.

The Lego/glue gun double act stemmed from a university project aimed at looking into making products from just one 3D printing filament, to make end of life recycling a relatively simple matter, as opposed to multi-material products that can pose a recycling challenge.

Before embarking on his Lego adventure, Patel did some preliminary work using the university's UP 3D printers to find out if he could incorporate zones of different stiffness into his single material objects. Though this proved possible, the layer by layer approach was found limiting and modeling and programming robotic assistance for extrusion along a path in multiple axes looked complicated, so he simplified the process.