The world of 3D printing is captivating, and for an engineering student with limited resources, the allure of creating something from scratch is even stronger. Inspired by the early Makerbot models but lacking the budget for a commercial 3D printer, this project documents the journey of building a functional, albeit rudimentary, Lego 3d Print machine from readily available LEGO bricks and components. This endeavor, spanning a year, resulted in a prototype 3D printer that uses hot glue as its printing material and is constructed almost entirely from LEGO Technic parts.
Early attempts to control motors using Arduino boards and parallel ports proved challenging, often requiring specific tools or parts that were inaccessible. Turning to a box of LEGOs offered a creative solution. The design of this lego 3d print concept draws inspiration from the original Makerbot, employing a similar Cartesian coordinate system. While capable of printing, it’s important to emphasize that this is more of a proof-of-concept and less of a polished, finished product.
Currently, the lego 3d print machine relies on four separate power supplies – 3V for the extruder motor, 7.2V for the NXT brick (which acts as the controller), 12V for a cooling fan, and 115V for the hot glue gun. Extrusion is manually controlled, a feature that is currently being upgraded for automated operation. A significant limitation lies in the programming aspect. Due to limited coding expertise, every movement must be programmed manually using the LEGO NXT software, as a compatible G-code interpreter for the NXT is still elusive.
Future iterations of this lego 3d print project aim to address several key areas for improvement. Reducing the height of the printing platform and minimizing wobble are primary goals. Integrating G-code compatibility would also be a major step forward, enabling the printer to utilize standard 3D printing software and designs. In the meantime, a Lego Digital Designer (LDD) file of the printer’s design is available, offering a detailed look at its construction. The digital model accurately reflects the Technic parts used in the physical printer, with minor structural adjustments made in the LDD file to streamline the digital building process while maintaining the same dimensions. To counterbalance the weight of the motors on the X and Y axes, suspended blocks containing coins are ingeniously incorporated into the design. A lens adjustment motor salvaged from an old VHS camera serves as the extruder motor, chosen for its low speed and high torque characteristics. The green case visible in the LDD file houses the extruder gears and functions effectively.
While hot glue serves as a functional printing material, its rubbery nature limits its practical applications. Thin, single or double-layer prints can adhere to glass, creating window stickers, but the resulting objects lack rigidity and durability. Future experiments are planned to explore alternative printing materials such as wax and heat-melting resins, which could offer improved material properties. Current material limitations are dictated by readily available resources. Increased accuracy could be achieved through the incorporation of more 3D printed parts in the lego 3d print design itself. Initially, a shortage of gear racks was overcome by enlisting the help of someone with access to a conventional 3D printer, who printed approximately 30 gear racks. However, these printed racks do not perfectly mesh with LEGO components, contributing to some platform wobble.
This lego 3d print project, born from ingenuity and resourcefulness, has garnered attention. It has been featured on prominent tech news websites like Technewsdaily, Gizmag, Hackaday, and Dvice, highlighting the innovative approach to 3D printing using LEGO. The project serves as an inspiring example of what can be achieved with creativity and readily available materials, even on a student budget.
