Future RepRap: Minerals & Printables
Ok, so a little esoteric, but I'm writing about the RepRap project, which is an open-source movement based on the idea of making 3d printers that can self replicate. In this discussion, 'minerals' refer to the parts that cannot be 3d printed but must be ordered or found. The 'printables' are those parts that the finished printer can print for the next generation machine.
A visit to RepRap.org is always a great way to see some of the many designs out there. There is so much, in fact, that the overall vision can become confusing at times. It helps to circle around to the landing page and re-read some of the founding statements about the project. Of particular interest is this one:
RepRap is about making self-replicating machines, and making them freely available for the benefit of everyone. We are using 3D printing to do this, but if you have other technologies that can copy themselves and that can be made freely available to all, then this is the place for you too. -RepRap.org landing page
I think it is interesting that the founders acknowledge the place for non-3D printed technologies in pursuit of having self replicating machines. This essentially sets the stage for the ongoing use of minerals as well as printables in the project.
For clarity, again, the 'minerals' involved in a RepRap are the things you cannot turn around and print with the finished machine. These traditionally are things such as the microcontroller, the wiring, the motors, the hotend, linear bearings, and the larger structures of the machine body, particularly anything that must be heated. The printables tend to be the mechanical corners, brackets, and rigid assemblies that hold the minerals.
Progress in the world of RepRap development has been in two distinct directions:
All print, no Minerals: On one hand, designers are working to move more minerals into the world of printables. A notable development in this direction has been with systems that mill blank circuit boards in order to create a new 3D printer controller. There are also some open source pick & place systems for assembling the components on the board. I have also personally experimented with making 3D printable Nema 17 motors for repraps, with varying degrees of success.
All Minerals, no Print: On the other hand, there are RepRap designs that strive to use as little 3d printed material as possible, so as to make assembly rapid with easily available materials. The RepRap project that I created for the Pueblo City-County Library District, the Libro, was focused on making a printer that could be created with only hand tools in a library setting. The minerals had to be of a sort that could be cut and assembled with only hand tools. The printables had to be kept to a minimum so as to be a reasonable load on the library's overused Makerbot Duo.
I think the most compelling RepRap designs are those that marry the two desires in some way that addresses a particular human tech ecosystem. My newest project involves an improved version of the Libro, which will be called the Ready RepRap. It will be an attempt to further reduce the 3D print times, while making use of hand-tool-only assembly with low cost minerals. It is designed for anyone of any experience level who can order few parts off of the internet, and then visit Home Depot for the rest of the parts. That's my personal tech ecosystem. If I was designing something to be made in subsaharan Africa, I would need to study what minerals are commonly available there.
Corollary question: Could we ever see a 'fully printable' RepRap, and if so, could the feedstock be highly available, or would it be so special that it would negate the 'freely available to all' aspects of RepRap's purpose?