In the early days of FDM 3D printing, innovation knew no bounds, and the RepRap project was at the forefront of pushing boundaries. Fast forward to today, and [dizekat] takes us on a nostalgic journey with the Marionette 3D printer, a machine that ditches conventional linear rails in favor of an intricate web of strings.
Remember the days when 3D printing was all about experimentation and unconventional designs? The Marionette 3D printer takes us back to that era. Instead of relying on linear guides, this unique creation utilizes strings to achieve precise movements.
The Marionette’s ingenuity lies in its simplicity, yet complexity. Its only resemblance to linear guides is a sheet of glass against which the print head glides. This printer employs a pair of stepper motors to navigate in the XY-plane, akin to the Maslow CNC router. But here’s where things get interesting: two more strings come into play to maintain tension in the system. Adjusting the string length across the printer’s full range of motion is achieved through an intricate articulating pulley mechanism. These strings are also positioned at a slight angle, ensuring the print head stays firmly against the glass surface.
A Bed Suspended by Strings
Not stopping at the print head, the Marionette also suspends and constrains its print bed using strings, eliminating the need for rigid mechanical attachments. Six strings are strategically connected to the bed frame’s sides and bottom, providing 6 degrees of freedom (DOF). They pass through another pulley arrangement, connecting to three more strings, which ultimately link to a single stepper-driven belt.
The Unconventional Choice
You might wonder why anyone would opt for strings over traditional linear rails, especially given the complexity of the Marionette’s mechanisms. While the advantages might not be immediately apparent, it presents an intriguing engineering challenge. Watching the Marionette in action is a captivating experience, and it produces prints of commendable quality.
The Marionette 3D printer is a testament to the boundless creativity that fueled the early days of 3D printing. Its reliance on strings instead of linear rails may raise eyebrows, but it serves as a captivating engineering marvel. Whether it’s for the sheer novelty or the potential to transform large-scale printing, the Marionette reminds us that the world of 3D printing is always evolving, and sometimes, looking back can lead to exciting discoveries.