Hello everybody!

I have been reading posts here and designing my own CNC for a while now. I have been sitting on this and not continued for quite some time, but I now have the opportunity to access a lathe and a well-equipped workshop for a couple of months, so I want to finally move this forward.

Before I go into the design, I want to quickly state what I want to achieve with this machine: I want a relatively large (read: Around 1m x 0.7m x 0.1m) area machine to cut wood, plastics and aluminium. At the same time I really want to constrain the cost as much as possible, not wanting to go over a cost of 4000€ (at this point I should probably mention that I am located in Germany).

Now with the information I have gathered, this is the design i came up with to satisfy these requirements:

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The Profile is Motedis 45x90S B-Type Slot Aluminium Profile, The rails are HIWIN rails and I am planning on using ballscrews for the motion. For the Rails and Screws I plan on buying a bundle on Aliexpress which will likely dictate the exact dimensions of the machine.

Now to the questions I am still having:
  • How would you go about connecting together the Profiles? Would angles suffice, or do you use something else there?
  • What would be the best way to mount the Rail Bearings? The green elements in my Model are just placeholders, since I struggle to find a good way to mount them.
  • How would I place Drag Chains on this design, to protect the cables? Would I need to make sure to have extra flat space to route these?
  • I was planning on using NEMA 34s with Timing belts to drive the screws. Would I need two of them for the Y Axis?
  • The Spindle Plate hanging on the Gantry looks huge to me, compared to the rest of the machine. Did I misdesign this?
  • Is a machine like this even capable of milling Aluminium? Would it be able to cut thin (not more than 10mm) steel sheets?
  • And finally, is this design even any good? I mostly worked off the information I found in various posts on this forum, especially for the gantry design, but I have no idea if the result has any glancing flaw.


Thank you for any help!