This is my first experience with RepRapFirmware and the Duet 2 Wifi. I am coming from a Marlin/Prusa firware based system. For reference, I am using a BLtouch 3.1 with firmware version 3.1.1. Everything is basically working, I just have a few things I am trying to understand a little better.
The printer is a modified Prusa MK3 Cartesian printer (bear frame). The heatbed is the MK52 PCB heater bed. As is common with this bed type, it tends to be not perfectly flat and changes shape a bit when heated. I will be using G29 mesh compensation.
So, to the questions...
I have followed the procedure to set the trigger height to be used in G31 in config.g, This should set the physical distance between the nozzle tip and the probe tip. This is not something I expect should change.
However, once set, I find when the bed is warmed up, I can either wind up too close or too far from the bed. Since this is somewhat dependent on the bed temperature, is there a better way to probe to compensate for this slight variation before generating the mesh for the bed compensation so I don't have to babystep at the start of every print? Would using a G30 S-3 temporarily change the trigger height? If so, does this offset persist until it changes again?
Does homing Z with the G30 change the trigger height or otherwise create an offset?