At this point I have been using the lazy/impatient mans speeds and feeds. I would like to start pushing to see where the limits are, but I would like to do it in a controlled manner.
So in a nutshell how should a person test up a speed and feed test
I did see a tool pressure calculation in a speed and feed calculator is that a rough indicator so for a given diameter of tool staying under x lb of tool force.
Gonna promote myself here, it’s 2000mm/min, 6mm DOC, 25 000 RPM with a 2-flute 6mm endmill.
Very fast is possible with a finishing pass, but it sounds like rats being put in a blender. 
Nice. Default current (0.7A?), regular TMC2209 drivers and 84oz steppers?
Eh, I think 1.5A, TB6600 (shitty drivers btw. Would now pay more to get better ones, but they are really old now as well…) and 84oz steppers. Maybe only 1A. It doesn’t make a difference though, I went as fast with smaller steppers as well. 
The limit is the flex in the LR.
@jamiek has a gcode generator that can generate "hog out " tests
https://vector76.github.io/gcode_tpgen/
