Universal CNC Axis
- 1 Intro
- 2 Development
- 3 5/16" Universal Axis
- 4 Simplification - From Clamshell to 1 Piece
- 5 Applications of 5/16" or 8 mm Universal Axis So Far
- 6 1" Universal Axis
- 7 2" Universal Axis
- 8 Universal Axis Development Directions
- 9 Example of CNC Circuit Mill Configuration, 5/16" Axis
- 10 Intro
- 11 Universal Axis - Working Document
- 12 Concept
- 13 WebGL
- 14 Build
- 15 BOM
- 16 Order
- 17 CAD
- 18 Fabrication
- 19 One Axis Attached to Frame
- 20 See Also
- 21 Communications
- 22 Industry Standards
- 23 Links
- The Universal Axis is a modular and scalable (easy to 200 lb tool force at 10 micron precision, larger with modifications on the basic system) CNC axis which can be used to create cartesian CNC machines. We have so far prototyped 8 mm, 1", and 2" rod versions of this. The core of the axis is belt drive and linear motion rods where carriages are pulled on the rods. The axis system may be used for the X, Y, and Z axes of cartesian robot system. The system is scalable to any size and number of axes. Rotary axes may also be used with this system The system uses a combination of 3D printed parts, metal plates, and belt-driven shafts. Applications include 3D printers, CNC torch tables, heavy duty CNC machines, and many other production machines.
- Both the belts, drive pulleys, and linear bearings may be 3D printed. This remains as future work.
- Force limits - the universal axis does 50 lb precision force (10 micron resolution using 16 microstepping and 1/2" diameter pulleys) per 15 mm wide high precision GT2 belt strand with nema 23 motors. So in practice we can safely get up to 600 lb of precision drive force if we use 2-sided drive (like Y1 + Y2), 2 motors per axis, 3 belts per axis. Screws can be used for higher force. If we want more than 600 lb force with belts, we could use belts other than the tiny GT2 belts.
- Applications - precision machining, automation, digital fabrication construction sets. A generic platform for precision motion and linear actuation.
5/16" Universal Axis
There are 14 unique parts in the Universal Axis:
We have built up to a 2 Meter Tall 3D Printer and a 1 cubic meter 3D printer using the 8 mm (5/16") Universal Axis:
Simplification - From Clamshell to 1 Piece
Applications of 5/16" or 8 mm Universal Axis So Far
1" Universal Axis
So far it was used to prototope a CNC Torch Table in 2018:
It interoperates with the 8 mm axis:
2" Universal Axis
See 2" Universal Axis.
Universal Axis Development Directions
Current Work - Universal Axis Designer in FreeCAD
Example of CNC Circuit Mill Configuration, 5/16" Axis
See full documentation at D3D CNC Circuit Mill
The following is a 5/16" or 8 mm version of the universal CNC axis described at http://opensourceecology.org/3d-printer-construction-set-workshop/
Larger axes will also be built, up to 2" for heavy duty CNC machining, with plastic parts sandwiched between metal plate as a plastic/metal composite structure. See calculations for beam deflection at Heavy_Duty_CNC_Construction_Set.
Universal Axis - Working Document
- P1 - Visual Linked BOM (VLBOM)
- P2 - extruder stepper motor mounting
From Michel Dhoore in Belgium in 2016. Early prototype using larger carriage pieces for larger machines.
FreeCAD and STL Files for Printing
See 3D Printer Part Library for all printer parts.
Originals from 2016 by Michel Dhoore
This file has the carriage belt tensioners, not shown below.
Universal Axis with Magnet Holes 2017
- File:Universal axis carriage side.fcstd. File:Universal axis carriage side.stl.
- File:Universal axis idler side.fcstd. File:Universal axis idler side.stl
- If using 6x10x3 mm flanged bearings (See BOM), then need a 1 mm spacer: File:Idlerspacer.fcstd. File:Idlerspacer.stl
- Print time - 3hr27min for the idler end -
One Axis Attached to Frame
- This one appears to be open source - , but has about 4x the unique count and lacks scalability and right angle connection ability.
- 3D Printer Manual - first application of the Universal Axis
- OSE Germany appears to be doing non-coordinated development on this for their Universal Prototyping Kit. 
- 3D Printer Design Evolution
- 3DP Construction Set workshops - December 2016 - 
- 1" Universal Axis
- 2" Universal Axis
- Open Source Digital Fabrication Construction Set