Cura 4.8.0 ; gcode temperature changes inconsistent with setup configuration

[KC1SA 0]

I'm somewhat new to multi-extruder 3D printing.  I've creating three object and assigned them each unique filament color, then merged them and sliced the object.  I have the Material temperature set to 214C for all parameters including the standby temperature, the build plate to 60C.  I've double checked the preference profiles and the printer profile to make sure these temperatures are the case.

I did a print and noticed the nozzle temperature was being set to 204C, then back to 219C.  I reviewed the gcode Cura generated and sure enough, there are these settings in the gcode.  Why?  What hidden settings am I missing?

 

Here's my startup gcode in the file;

;FLAVOR:Marlin
;TIME:2845
;Filament used: 1.53852m, 0.649219m, 0.543324m
;Layer height: 0.2
;MINX:147.347
;MINY:150.2
;MINZ:0.15
;MAXX:300.6
;MAXY:305.6
;MAXZ:19.95
;Generated with Cura_SteamEngine 4.8.0
T0
M140 S60
M105
M190 S60
M104 S214
M104 T1 S214
M104 T2 S214
M105
M109 S214
M105
M109 T1 S214
M105
M109 T2 S214
M82 ;absolute extrusion mode
G28 
G1 Z15 F300
M107
G90
M82
M104 S214
M140 S60
G92 E0
M109 S214
M107
M163 S0 P0.33
M163 S1 P0.33
M163 S2 P0.33
M164 S4
G0 X10 Y20 F6000
G1 Z0.8

 

But then this;

 

G1 X149.2 Y160.55
G1 F1200 E-3.23499
G1 F600 Z5.35
G92 E0
T0
G92 E0
M104 T2 S204
G1 F1200 E15
G1 F600 Z4.35
;MESH:cutbottom.stl
G0 F4800 X292.8 Y284.5
G0 X291.799 Y284.5
;TYPE:PRIME-TOWER
G1 F2100 E16
G1 F3600 X291.562 Y286.90

 

Regards,

 

Steve

 

[tinkergnome 927]

1 hour ago, KC1SA said:

What hidden settings am I missing?

 

[KC1SA 0]

not these... these are all set to 214C.

 

[KC1SA 0]

I double checked and sure enough these are all set to 214 so why is this code in my g-code?

1 F1800 X169.622 Y157.177 E33.99899
G0 F7200 X170.264 Y157.254
G1 F1800 X170.775 Y157.764 E34.017
G1 F1200 E18.017
G1 F600 Z6.55
G92 E0
T0
G92 E0
M104 T2 S204
G1 F1200 E15
G1 F600 Z5.55
;MESH:cutbottom.stl
G0 F7200 X289.421 Y279.291
G0 X289.887 Y280.19
;TYPE:PRIME-TOWER
G1 F2100 E16
G1 F3600 X291.8 Y280.002 E16.04795
G1 X293.713 Y280.19 E16.0959
G1 X295.55 Y280.747 E16.14378
G1 X297.24 Y281

[Torgeir 247]

Hi there,

 

Excuse me, but is not T0 core 1, T1 core 2 and T2 the heat bed?

 

(The digital world and hexadecimal numbers.)

 

Looks like core 1 (T0) is missing here..

 

Sure sometimes I'll got confused for sure..

 

Torgeir

Edited March 17, 2021 by Torgeir
More text.

[KC1SA 0]

In a three extruder machine the extruders are T0, T1, T2.  At least that's my understanding.  When I send manual G-codes those are the 'tools' I select to move filametn.

 

[Torgeir 247]

Well, I cannot see that T0 is active.. Is it really selected?

 

If you attach your project file here, it will be a lot easier for any of us to investigate in order to help..

(Use save project file).

 

Thanks

Torgeir.

[tinkergnome 927]

4 hours ago, KC1SA said:

not these... these are all set to 214C.

 

for all three extruders...?

[GregValiant 1,287]

It would be helpful to know what printer as well.

Those are long retracts and primes.  Is it a "3-in-1-out" hot end?  That would require "Extruders Share Heater" to be checked.  Selecting each extruder in turn, you should be able to set the Printing Temp, Initial Printing Temp, and the Standby Temp for that extruder.

 

I set up a 3in1out machine in Cura.  Setting all 9 temperature settings results in a single M104 at the start of the file and "M104 S0 ;turn off hot end" at the end of the file.  That is with each extruder assigned to a separate part.

[KC1SA 0]

Ok. I uninstalled all the versions of Cura I have on my laptop.  I very carefully added my profiles.  What I may have done in the previous installation is NOT set up the extruder temperature for all THREE extruders.  This time around I made sure they are all set to the right temperature and I have success.... at least once. :-).

 

I set all the hotbed temperatures to the same value.  This is a Geeetech A30T, so it has three extruders (T0, T1, T2) but only one hot end.  I still have to set the temperature for all three extruders even though there is only one hot end.  That is fine, ideally it allows you to run slightly different plastics in each extruder, but in practice Geeetech recommends use all the same temperature plastics in the three extruders.  

 

So I have success and thank you for making me doubt myself on the set up, sometime we can't see the forest for the trees.

 

Now I have another small issue.  I did a slice using one of my profiles, which I have to make sure I didn't do anything stupid.  I did look at all three extruders and they are all identical with the same temperature settings.  This one slice I added support  which I haven't experimented with yet on this machine.  When I printed, after the first layer the extruder turned off. Hmmmm.  So I looked at the g-code and it looks like the slicer inserted a shut down of the hot end right after printing the first layer.    Again, this is the same profile that worked fine, just I added support this time around.  I'm using he middle extruder only (T1), here's and excerpt of the g-code;

 

 

;Generated with Cura_SteamEngine 4.8.0
T0
M140 S60
M105
M190 S60
M104 S214
M104 T1 S214
M105
M109 S214
M105
M109 T1 S214
M82 ;absolute extrusion mode
G28 ;Home
G1 Z15.0 F6000 ;Move the platform down 15mm
G92 E0
G1 F200 E3
G92 E0
G92 E0
G92 E0
G1 F2400 E-6.5
;LAYER_COUNT:275
;LAYER:0
M107
G1 F600 Z1.3
G0 F2400 X158.493 Y131.104 Z1.3
;TYPE:SKIRT
G1 F600 Z0.3
G1 F2400 E-0.12473
G1 F1800 X158.876 Y130.666 E-0.0957
..
..
..

G1 F600 Z1.3
G0 F2400 X290 Y290 Z1.3
G1 F1500 E-1.97648
G1 F600 Z1.3
G92 E0
T1
G92 E0
M104 T0 S0  -- Why did the slicer insert this?
G1 F2400 E-6.5
G0 X290 Y290 Z1.3
G1 F600 Z1.3
G0 F2400 X180.731 Y149.227
;TYPE:SKIRT

[GregValiant 1,287]

You are sure that "Extruders share heater" is checked?  In Cura 4.8 it is in the "Printer Settings" which must be loaded from the Marketplace.

[KC1SA 0]

I guess that's why that classify you as an expert, I'm just a hacker..   Thanks for the advice, I'll have to check that

[GregValiant 1,287]

It was easier to find in 4.7.  If it isn't checked you get what you got - extruders shut off when they won't be used again.  When it is checked you'll get what you want - the extruder heater stays on until the end.

[KC1SA 0]

Yes,. that looks like it eliminated the issue.  Thx.