Instructables user Matthew Kreuger built this Lego 3D printer that prints using hot glue.
Ever since I saw the first makerbot, I have been obsessed with 3D printing, but I am an engineering student so I don’t have an extra $800-$2500, and have been doing my best to create one out of what I have on hand. I tried arduino with easy drivers, and parallel port, but neither one gave results, I always needed a tool or part that I couldn’t get. So I pulled out my old box of legos and started building.
This is a project I have been working on for the past year, it prints in hot glue and made almost completely out of legos. Based roughly on the first version of the makerbot, while it does print, I would call this more of a prototype than a finished project. I am using 4 power supplies (3v extruder, 7.2v for nxt, 12v fan, and 115 for hot glue gun) and having to manually turn the extruder on and off, (although i am working on that one) . Unfortunately, due to my lack of computer programming skills, every move has to be manually programmed from the NXT programming software, I have yet to find a g-code interpreter for the NXT.