I've spent the evening working with estep calibration on my UM2+
Below are the results. I hope you understand the data 🙂
The time the extruder ran was as perfect as I could measure each time. (And it seems my response time is always very close to 0.15 seconds 😉 )
First of all a notice on what I assume is some kind of bug. The first extrusion run after every M92 change of the estep value, gives a way off result.
So, I have tested three extrusion lengths 100mm, 200mm and 300mm. It seems the longer extrusion run, the less filament is extruded. So, at the third and last setting in