Cura 3.2.23+ Extruder Count Bug?

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radensb
Posts: 39
Joined: Sun Jul 23, 2017 3:21 pm

Cura 3.2.23+ Extruder Count Bug?

Post by radensb » Mon Sep 10, 2018 3:45 pm

I upgraded to Cura 3.2.23 today and set up my machine. I have a TAZ6 with v3 dual extruder.

Previously in 3.2.21, I had two machine profiles defined. Both were TAZ6 with V3 Dual Extruder profiles, however, one of the profiles was named "LULZBOT TAZ6 DualExtruderv3 (T0 ONLY)" and had the gcode start and end blocks modified with all the commands for T1 removed. I used this machine profile when I didnt need both extruders active for a simple print. When I wanted to use both extruders, I used the standard LULZBOT TAZ6 DualExtruderv3 machine profile. This worked well, since there is no way to toggle dual extruder support easily. However, after the upgrade, I noticed that a print paused and started heating the second extruder (T1) right after the modified gcode start block was executed. I double checked the block and confirmed that all the T1 related commands were commented out. Then I checked the gcode file for the print and noticed that T1 gets set right before the skirt gets printed.

Original code from 3.2.21:

Code: Select all

[b]<... end of start gcode block...>[/b]
M117 TAZ Printing...         ; LCD status message
M221 S100
;LAYER_COUNT:94
;LAYER:0
M107
G0 F3600 X113.759 Y111.408 Z0.299
;TYPE:SKIRT
G1 F1800 X114.246 Y111.158 E0.01283
Code from 3.2.23:

Code: Select all

<... end of start gcode block...>
M117 TAZ Printing...         ; LCD status message

M221 S100
;LAYER_COUNT:75
;LAYER:0
G1 F600 E-5
G92 E0
T1
G92 E0
M109 S210
M107
M104 T0 S180
G0 F2250 X98.526 Y102.226 Z0.424
;TYPE:SKIRT
G1 F900 X98.712 Y101.971 E0.01049
In the code from 3.2.23, there are commands for T1 added now! So, I tried modifying the number of extruders in the Machine Settings for (T0 ONLY) from 2 to 1 hoping that this would eliminate the generation of gcode for T1, but when i went to slice, Cura crashed with an error message that states "CuraEngine.exe has stopped working". So, its clear that setting the number of extruders to 1 on a machine profile setup for dual extruders puts the program in an invalid state. This behavior is also present in the newest 3.2.27 version. What was the reason for adding these commands? Is there a way to prevent them from generating or can this be addressed in future versions!!??

radensb
Posts: 39
Joined: Sun Jul 23, 2017 3:21 pm

Re: Cura 3.2.23+ Extruder Count Bug?

Post by radensb » Mon Sep 10, 2018 4:59 pm

I have confirmed that setting the number of extruders from 2 to 1 in 3.2.21 also causes the program to experience the unhanded exception. Also, after re-reading the release notes, the added T1 commands may be due to the following note under Bug Fixes:
- Fixed TAZ 6 start gcode which was ignoring initial layer temperature setting

It seems like the solution here is to correct the bug that causes slicing to fail with only one extruder enabled and that the proper gcode gets generated. In the meantime, I will continue with 3.2.27 and just manually remove the couple of instances the T1 command is used with a bit of manual post processing....

radensb
Posts: 39
Joined: Sun Jul 23, 2017 3:21 pm

Re: Cura 3.2.23+ Extruder Count Bug?

Post by radensb » Mon Sep 10, 2018 5:40 pm

Another update...

Ok devs... now I'm really confused. After reinstalling 3.2.27, I am generating gcode without the T1 commands just like I did in 3.2.21..... I am at a loss as to why it is working as I expect now. In all cases, I performed a clean installation with previous files cleared out as instructed. I guess if anyone else is seeing this happen, try uninstalling and reinstalling the program? Still, the extruder count bug should be addressed.

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