https://dirstop.com/story28123131/the-4-axis-cnc-router-a-the-thorough-explanation
The 4-Axis CNC Router: A The Thorough Explanation
4 axis cnc routerthoroughexplanation
https://hackaday.com/2014/10/06/4-axis-cnc-foam-cutter-sports-a-unistrut-frame/
4 Axis CNC Foam Cutter Sports A Unistrut Frame | Hackaday
Aug 24, 2015 - CNC Foam Cutters are capable of cutting out some pretty cool shapes that would otherwise be extremely difficult to do. They do this by pulling a heated metal...
4 axis cncfoam cuttersportsunistrutframe