Regardless of whether you want to 3D print your own parts or make a LongMill completely from scratch, we offer all of the designs available for the LongMill for free under a Creative Commons BY-SA license.
You can find them in our resources page on Open Source.
For technical specs, warranty, and more, visit the LongMill Product Page.
All of our files are on OnShape, which means that you may need to export them as STL files directly from our project files. You can also find more details about our printing settings here: https://sienci.com/2019/11/11/3d-printing-settings-for-longmill-parts/