Z offset after levelling changes

[coddiewomple]

After setting a nice Z offset at the right temprature for the filament in use using some feeler gauges range between 0.5mm, 0.10mm, 0.15mm aiming for 0.10mm maybe 0.12mm for petg thn send printer through automatic mesh process and once completed return to leveling start screen but the nozzle is always returned lower than set at the start and this is in the middle of the bed the safest levellest place?

so the Z offset gap changes drastically all the time but the z offset indication in the screen reports no change to accoutn for it and why would it for nobody has told it to change!. There are no loose parts or any play so why is this happening?

Also every time entering the levelling screen to check z offset gap it varies so much i could set a gap of 0.1mm using gauge for accuracy and then find it has moved to 0.2mm gap because it wanted to!

The only play on the machne at all is in the brass lead screw nuts and elegoo have told me there is no need to change those and so none are available.

[HonzaMiki]

Hi, I understand your problem, today I updated my issue and answered your question, could you check it, if you have this problem? I attached some videos and tutorial. Thank You.