"Big Yellow" DIY CNC mill: Converting a Proxxon MF70 mini-mill to CNC with 3D printed parts

I love making things, and I have 3D printed all kinds of things, both functional and decorative, for a long time. However, 3D printing's biggest limitation is that as far as what is feasible to do at home, you are mostly restricted to working with various forms of plastic. The things you print look plasticky, feel plasticky, and are also limited to the durability of plastic. Don't get me wrong, 3D printing is awesome. But I've always wanted to get into CNC because you can make things out of real metal and wood.

In addition, after learning much about diffusion- and NeRF-based text-to-3D pipelines such as MVDream, I realized that modelling decorative 3D items is about to become a lot easier, and I wanted to have a way to turn these meshes into real objects.

And so I decided to build my own CNC mill, by 3D printing parts to modify a Proxxon MF70 mini-mill. It's the smallest mill you can buy, costs only $400 (~$300 if you can snag an open box one on eBay), is perfectly sized for small hobby projects, and has been the subject of numerous DIY CNC conversions on the internet. I was not happy with any of them, for many reasons, so I decided to design my own conversion from scratch. Despite the deficiencies of this small, cheap machine, the journey of modifying this for CNC taught me a LOT for the $600 I spent in total on it. The machine turned out to be far more capable than I expected it to be, and I will probably use it for quite a while.

Head over to the Github repo for plans and build instructions.