Where does the initial bed and hot end temperature setting come from and how can I remove it?  

Where does the initial bed and hot end temperature setting come from and how can I remove it?

Hello!

I have a Jubilee tool changer that I am using PrusaSlicer with (before I get my Prusa XL :-D).  I have a new printer configuration that I put together from scratch.  For the most part, I've been referencing the PrusaSlicer documentation, as well as Bob George's excellent project notebook.

I have a filament called "None", with a first layer and print temperature of 0, and a bed temp of 85 (I mostly print PETG).  In an ideal world, I would like the printer to go through the following sequence:

1) Set and return control to host heated bed temperature
2) Set all hot ends that are loaded with filament that's used in the print to standby-40 deg C (to prevent oozing)
3) Do all the homing / probing, while the printer heats up
4) Set and wait for the hot ends to standby temp (Generally equal to print temp in my case, can change for exotic support materials)
5) Wait for the HBP to get to printing temperature.

I have most of this G-Code written in the Custom G-Code section for my Jubilee printer profile, under "Start G-Code".  However, on exporting the code, this is what's generated:

; generated by PrusaSlicer 2.3.3+win64 on 2021-12-18 at 22:12:00 UTC

; 

; external perimeters extrusion width = 0.45mm
; perimeters extrusion width = 0.45mm
; infill extrusion width = 0.45mm
; solid infill extrusion width = 0.45mm
; top infill extrusion width = 0.40mm
; support material extrusion width = 0.35mm
; first layer extrusion width = 0.42mm

M107
M190 S85 ; set bed temperature and wait for it to be reached
G10 S250 P1 ; set temperature
;TYPE:Custom
; PrusaSlicer start gcode for Jubilee 
; Last updated: Dec 18th, 2021

M300 S60 P10; Chirp

M117 Initializing...

; Set Coordinate Mode;
G90; Use absolute coordinates
M83; Extruder in relative mode

; Reset speed and extrusion rates
M220 S100 ; reset speed back to 100%
M221 S100 ; reset extrusion rate back to 100%

; Set initial warmup temps
M117 Nozzle Preheat
 ; Set standby temp to 40 deg below printing temp to prevent oozing, set print head to "standby" state
M568 P0 R0 S0 A1  ; Set standby and print temp to 0, print head to "standby" state.
M568 P1 R210 S250 A1  ; Set standby temp to 40 deg below printing temp to prevent oozing, set print head to "standby" state
 ; Set standby and print temp to 0, print head to "standby" state.
 ; Set standby temp to 40 deg below printing temp to prevent oozing, set print head to "standby" state
 M568 P2 R0 S0 A1  ; Set standby and print temp to 0, print head to "standby" state.
 ; Set standby temp to 40 deg below printing temp to prevent oozing, set print head to "standby" state
 M568 P3 R0 S0 A1  ; Set standby and print temp to 0, print head to "standby" state.
G28 ; home all axes

 ; Set standby temp to printing temp, set print head to "standby" state
M568 P1 R250 S250 A1  ; Set standby temp to printing temp, set print head to "standby" state
 ; Set standby temp to printing temp, set print head to "standby" state
 ; Set standby temp to printing temp, set print head to "standby" state

G1 Z5 F5000 ; lift nozzle

G21 ; set units to millimeters

G90 ; use absolute coordinates

M83 ; use relative distances for extrusion



G10 S250 P1 ; set temperature
M116 ; wait for temperature to be reached
G21 ; set units to millimeters
G90 ; use absolute coordinates
M83 ; use relative distances for extrusion

My questions are:

1) Where does the initial M190 S85 right after all the Prusaslicer settings comments come from, and how can I remove it?  I would prefer not to call an M190 at this point; I would much prefer to call M140 instead, and calculate the heated bed temperatures based on the maximum of the 4 heated bed temperatures in the filaments selected.  A M190 called at this point basically pauses the printer for a good 10-20 minutes, as the Jubilee has a 300mm x 300mm HBP that takes a while to get to temp.

2)  Same for the G10 S250 p1; my understanding is that G10 for setting tool temp is being deprecated in Reprap firmware, the preferred method is calling M568 P# R{standby_temp} S{print_temp} A{0-2} based on which mode you want the tool to settle into (off, standby, or printing)

3)  Where does the G10 S250 P1 come from after the "Start G-Code block" executes?  Again, I would prefer to change it to an M568 command.

4)  For my personal information, where is the linear advance (M900) set?

Thanks!

-=- Terence