Tool Force in Milling
Analysis of tool force indicates that feed force (force in the direction of feed) is only 20% of total tooling force. . This bodes well for belt-driven universal axes, in that a 100 lb tool feed force limit allows for 500lb overall tooling force limit?
Not clear. Tangential forces are 70%. If tangential in direction of feed, this does not help.
But - overall milling forces appear to be on the order of 100-200N, which is well within the capacity of GT2 precision belt drive.
Published Cutting Forces
- Analysis of published cutting forces shows only 100 Newton scale forces.  We have 5x this force allowance with the Universal Axis.
- Lathe - Here we have 50-100kg tool forces 
- Mill - 10 mm ball mill - up to 200 N forces - [file:///home/marcin/Desktop/jmmp-02-00035.pdf]
Machine Design Strategies
It may be useful to divide machining drive into 2 regimes: bulk and precision. GT2 is used for the precision part. Heavier belt may be used for bulk forces, such as in lathing.