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.
The extruder is made up of 112 Lego Technic parts including an electric 9 V battery box and a 9 V motor, five different sizes of toothed gear wheels, and numerous beams, connectors, axles, bricks and bushes. Once assembled and attached to the off-the-shelf hot glue gun, it feeds the filament through to the nozzle at a steady rate. Then the artist can work on the creation of objects like a fruit bowl, a bracelet or a helmet, with joints being secured by heating the filament where two filament lines cross.
Patel has posted extruder build instructions and a full parts list on Redbrickable for tinkerers who might want to try and build their own handheld 3D printing gun. You can see Patel putting together the extruder and some of the 3D-printed objects he's created so far in the video below.
Source: Vimal Patel