Switching colors mid print

[jaysenodell 13]

Nope. I'm wrong. commented out the G92 and it still snots the second the extruder moves out of the park location. I think this is an over pressure type situation in the nozzel. 

2 layer test - with pause less G92.gcode

[jaysenodell 13]

@GregValiant you can call me names publically. I am a self acknowledged moron. Look what I found in my Ocroprint "beforePrintResume" script...

{% if pause_position.x is not none %}
; relative extruder
M83

; prime nozzle
G1 E-5 F4500
G1 E5 F4500
G1 E5 F4500

; absolute E
M82

; absolute XYZ
G90

; reset E
G92 E{{ pause_position.e }}

; move back to pause position XYZ
G1 X{{ pause_position.x }} Y{{ pause_position.y }} Z{{ pause_position.z }} F4500

; reset to feed rate before pause if available
{% if pause_position.f is not none %}G1 F{{ pause_position.f }}{% endif %}
{% endif %}

Of particular note the section labled "prime nozzle". 

 

Upon remove (commenting) of those three lines all artifacts are gone. It still feels like I should use that section to print a starting line like cura does at the open of every print job, but for now I'm going to leave it well enough alone and stick with with @Slashee_the_Cow's support object. 

 

Thank you all for the help. 

[Slashee_the_Cow 267]

9 hours ago, jaysenodell said:

My understanding of the G92 is that it isn't supposed to MOVE the extruder but that is tells Marlin "please consider the extruder position is currenly X nd treat it as such". I believe Creality has overridden this behavior becuase ... why not? Do I properly understand G92?

You understand correctly. G92 tells the printer "<insert axis here> is currently at <insert value here>". Cura uses it to reset the E value to 0 every so often even with absolute extrusion on to avoid rounding errors snowballing into big problems.

 

8 hours ago, jaysenodell said:

stick with with @Slashee_the_Cow's support object. 

I'd love to take credit for that but @GregValiant actually showed me that trick 😄