Warmup improvement requested

[eldrick 56]

I'd like to ask for a small improvement in Cura's routine that warms up the UM2.

The thought is that it makes No sense to wait until the bed is up to the set temperature before starting to heat up the extruder - it just further extends the time to start a print.

I'm using the following code with Kisslicer to pre-warm the UM2 extruder while the bed is heating, and then to bring it up to set temperature at about the same time as the bed is ready:

G21 ;Metric Values

G90 ;Absolute Positioning

M82 ;Extruder to Absolute

M106 S0 ;Fans Off

G28 ;Home All Axes

G1 X5 Y10 F9000 ;Move Head to ~Origin

G1 Z20 F9000 ;Raise Bed to Head

M104 S ;preheat extruder

M140 S ; set bed temp to Lo

M190 S ;Wait For Bed to Reach Lo Temp

M140 S ;Set bed temp to final

M109 S ;Set & Wait Extruder Temp

G92 E0 ;Zero Extrude L

G1 F100 E18 ;Forward 18mm @ 100mm/min

G1 F50 E28 ;Extrude 10mm @ 75mm/min

G92 E0 ;Zero Extrude L

The and variables are used by KS to insert the obvious settings. The sequence is:

- preheat the head temperature to the final temperature minus 80 degrees,

- and set the bed temp to the final temp less 5 degrees,

- wait for the bed temp to get there,

- then set the head temp to the final,

- and also set the bed temp to final.

The net is that the extruder is ready to go at about the same time as the bed, rather than heating the two one after the other.

[DidierKlein 648]

What firmware is installed on your UM2?

Mine does what you describe, it starts heating the extruder when the bed temp is 5°c under the desired temp. (I'm using Tinkergnome modified firmware but i believe it's based on the 15.02 firmware.

[eldrick 56]

I'm using the latest version. Yes, it starts heating 5C before bed heating is complete, but it takes a while to get there.

If the head is pre-heated, it saves quite a few seconds before it starts to print.