Food for thunk: Using nozzle temp as stand-in for MINDA temperature sensor?
I don't have a Mini myself, but I've followed many of the discussions. I'm understanding that the lack of a temperature sensor on the MINDA is being blamed for inconsistent temperatures being used for probing. It looks like using fixed wait times is being used as a work-around. I realized that the temperature of an UNHEATED nozzle closely matches the temperature sensed on my Mk3's PINDA probe during warmup. Might the nozzle sensor be used on the Mini to work around this shortcoming?
There's unfortunately no way to implement this currently in Mini gcode so far as I know. M109 will wait for a temperature, but will heat the nozzle to the specified temperature. I can't test this, but would appreciate it if a Mini owner would confirm. I see 3 possible alternatives (in order of desirability):
- Assuming the Mini issues temperature status continuously over the serial port as is done on the Mk3, implement a script (an Octoprint plugin is a workable solution) to monitor the nozzle temp.
- M109 Sxx allows or is modified (perhaps with a different parameter than S) by Team Prusa to implement a "wait for UNHEATED nozzle temp".
- M860 Sxx used to wait for the PINDA on the Mk3 is implemented by Team Prusa on the Mini as "wait for UNHEATED nozzle temp".
This way, startup gcode could be modified to heat the bed, position the UNHEATED nozzle near the bed and wait for the nozzle to hit a consistent temperature (e.g. 35C as used with the PINDA) before starting mesh bed leveling.
It would also be very helpful if Team Prusa implemented messages in the startup gcode using M117 to let users know what is going on at each stage to avoid confusion with the 170C 2-step nozzle warmup and the delays that this process would introduce.
Thunks?