Prime Tower/Ooze Shield issue Cura5.2.1

[madurani 0]

Hello All,

 

I have printer with 4-IN-1-OUT Mixing Color hotend and use a Cura slider tool. Problem appear when I use mode "Dual extrusion". 

Prime tower still use extruder 1 on printing first layer of tower although isn't use in model. I don't know find in cura slicer any setting for it(a managing of which extruders will be use in firs layer).

 For example: I want print model where are use only extruder 3(white) and 4(blue). Cura begin build tower with extruder 1(black) and continue with using extruder 1 in some shield around tower and in Ooze Shield around model. Where is posible disable this strange behavior of cura?

 

The first extruder shouldn't be used, because this color isn't in model.

 

 

First layer:

 

Edited November 21, 2022 by madurani

[madurani 0]

Very temporary solution in my case when I want only disable/replace extruder1 with extruder3 was modify gcode
output file from Cura. I replaced it with sed command  extruder1(T0) with extruder3(T2) and were fixed:

 

grep T0 CFFFP_color2.gcode|wc -l 
6

sed -i 's/T0/T2/g' CFFFP_color2_sed.gcode
grep T0 CFFFP_color2.gcode|wc -l
0

When I print file via OctoPrint

[GregValiant 1,250]

I responded on Github and I'll rehash it here.

This looks like a bug to me as it doesn't matter if T0 is disabled or unused.  When the Prime Tower is enabled Cura switches to T0.  With the Prime Tower disabled it seems to work as it should with no references to T0.

 

I see you have a workaround.  The same thing can be done within Cura using Search and Replace post-processor:
Search = T0\n
Replace = T3\n
Use regular expressions = checked

The "\n" is a newline character and they are required as shown.

 

Whether it's done in Cura or Octoprint - it's a poor workaround as the movement code at the Prime Tower is still there and it isn't needed (or wanted).

Edited November 22, 2022 by GregValiant

[madurani 0]

I switched from Cura to Prusa Slicer😃, there aren't any problems with tower and multi color printing. 

Edited December 5, 2022 by madurani

[GregValiant 1,250]

I've been fooling around with Dual extrusion and the problem definitely exists.  If I start with extruder 1 there are 5 tool changes.  If I start with extruder 2 there are 68 tool changes.