Accuracy and Precision would be problematic with this design, but, lack of rigidity is more insidious. Most of these high speed spindles will use carbide toolin

Accuracy and Precision would be problematic with this design, but, lack of rigidity is more insidious. Most of these high speed spindles will use carbide tooling, which is highly susceptible to breakdown under vibration. A flexible horrible frame like this is going to vibrate a lot even in materials like delrin or HDPE. Also, with a vertical spindle and CNC control, there is no reason to have a vertical rotary axis. The reduced motion doesn't buy any capability upgrade. The 4th axis that is helpful would be angular. (you could put a horizontal spindle on this, I guess, but this machine is not up to the task.