Open-source CAD for full Public Release of the LongMill MK2 design files is finally complete!

The LongMill Benchtop CNC has finally seen a revitalization in the form of it’s new MK2 design. In development since late 2020, many aspects of the design were sought to be overhauled in the name of everything the LongMill projects stands for: low cost of manufacture, design simplicity, ease of assembly, and rigidity. With the MK2 all these improvements are brought further due to a complete re-imagining of what the LongMill could look like with a redesign from the ground up.

MK2 distinguishes itself from the original LongMill project by a couple key factors. Though many of the common components carry over such as v-wheels, lead screws, motors, anti-backlash nuts, etc. the biggest differentiator is the use of two completely custom designed extrusions for each X and Y-axes which allow for much higher rigidity, easy of assembly, reduced part count, and more rigid mounting of the Y-rails to the tabletop surface. The MK2 design was also further optimized by the shape of the X, Y, an Z carriage plates to squeeze more travel out of the same length lead screws while also increasing the CNC’s rigidity by how the v-wheels are located. The blank canvas of the MK2 also meant we could ensure that add-ons our customers have been enjoying on their existing LongMills could be make available on the MK2 with much simpler implementation such as dust shields, dust shoe, and limit switches.

With MK2s shipping out our doors starting April 2022 it took a couple extra months to get our CAD in order for public release but we also pride ourselves in doing as much 3D model clean up on our end as possible before public release so that the design files are more ‘open-source’, as open sourcing not only comes with making designs available, but the spirit of open-source is also to make resources for replication as accessible as possible to the average person.

Check out and browse through all of the MK2s parts and assemblies here: Onshape

Read more about our open-source project and other aspects of what you can download here: Open-source 🥽 - LongMill MK2 CNC

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Why was Onshape used as your choice of program? Why not pdf them to size so it is easier to print as a 11" X 17" size drawing (or shrink to fit) or save or the metric equivalent?
Thank You!

@Condor00 since it’s hard to predict how people will use our designs we just try our best to make as much available as we can with enough access that those designs can be used as needed and Onshape provides that. When you’re asking about to-scale PDFs that’d be an option for the plates but perhaps not for the machined, 3D printed, or extruded parts. Similarly we could try to provide detailed machining drawings or 3D printing g-code but those also would be making assumptions about printer or machine capabilities and so wouldn’t be guaranteed to work in most cases. Another thing to note is that some hole placements for the plates are required to be accurate to below 1mm, so a printed template would likely not carry the required accuracy.