Hi,
After calibration of the height and then a auto calibration, I stored the settings and started to print.
When the nozzle has been heated to 200 degrees it moves to a corner of the bed and starts priming very close to the bed at perfect height. When priming is done the nozzle head moves to the center, unfortunately the height calibration seems to be lost and the nozzle is no longer calibrated, the height from the bed to the nozzle is approximately 5mm which leads to a disaster.
What can be the reason for this?
This is just a guess.
Maybe your end stops are rather heigh. The problem are the soft-end-stops which just follow the value DELTA_HEIGHT in the firmware. If this is the case there are two solutions move the end stops 5 mm down, or increase the DELTA_HEIGHT in the firmware and upload it using the Arduino IDE.
Make sure your piezo sensors are not too sensitive, the red LED should blink only when the print head touches the bed, if it does blink when the nozzle is still above the surface decrese the sensitivity with the potentiometer.
