I've been planning to build a serious vertical CNC mill for a while now. I have a Sieg X2 which is pretty useful but every time I use it I have to deal with the small table, small travel, low rigidity, adjusting gibbs, imprecise z-axis positioning, low power, etc, etc. The new mill is designed to eliminate all of these problems as much as possible. The design considerations are as follows:

  • massive bed and column made of epoxy granite to improve rigidity and dampen vibration
  • move on linear guide rails on all axes (20mm or larger, no more gibbs!)
  • driven by ball screws (20mm diameter)
  • and large stepper motors (Nema 34)
  • much larger working envelope (~250 x 500 mm)
  • full size cat 40 vmc spindle (6000rpm)
  • powerful DC spindle motor (3hp)
  • pneumatic actuated draw bar
  • CNC as well as manual operation


Here are some drawings of the design I've come up with.
Attachment 268082 Attachment 268094 Attachment 268100
Attachment 268090 Attachment 268088 Attachment 268086
Attachment 268096 Attachment 268092 Attachment 268098
The z-axis head is not fully designed yet, the spindle motor and pneumatic cylinder are roughly placed!

All brown-ish colored parts will be made of epoxy-granite cement with internal steel reinforcements. Grey-colored components are steel or aluminum.

To give you an idea of the size, the vise sitting on the table is a standard Kurt 6" angle lock.

The base is ~ 250 x 460 x 880 mm with a weight of about 150kg.
The column is ~ 305 x 460 x 1090 mm and weighs also around 150kg
The saddle is ~ 95 x 240 x 820 mm and weighs about 50 kg.
The table is the same size as the travels, that is ~250 x 500 mm and will be made of solid steel.

The exact dimensions of the mill are given by the sizes of the linear rails and ball screws that I happened to have in my "collection"!

I will keep adding more posts as I make progress on the mill.

Any comments, suggestions or questions are welcome!