I am having a problem with my Flying Bear P902 3D printer where I have to calculate the Z offset for every single print. I calculate it using this method (and store it in EEPROM) : Link to Stackoverflow post. Then, it will be able to print the first print with the right layer height. But, when I upload a second print afterwards, something goes wrong. It levels the bed and it starts printing too far away from the bed so it is just printing in the air. So, it must some way not have measured right. I checked the Z offset on the control panel and it does say the right offset that I calculated (-2.3).
During the bed leveling, I do sometimes have a problem. It will try to move the bed up to touch the probe, and there is this loud screeching noise, and the bed will not move upward. But, other times it doesn't have this problem. And, I am not sure if this is related to the inconsistent bed leveling.
Printer: Flying Bear P902 (Powered by Arduino & Ramps 1.4) Auto Bed Leveling: BLTouch
Anyway, I have no idea what is causing this problem and it is really annoying to calculate the offset every time. Do you guys have any ideas? Have you guys experienced this problem?