Two-color printing error

[klickon 0]

Hello everyone.
I use 3D printer Geeetech Mizar M. I still have a problem with dual printing of two-color models that I slice in UltimaMaker Cura 5.4.0 software. I use Prime Tower for dual extrusion printing. This error appears whenever I print models such as the one in Picture1.

Slicer processed the model as I inserted it and assembled it from two parts and then merged it into one model. (Picture2) The printer works without problems as long as both colors are contained in the layer. The problem appears when there is only one color left to print (Picture3). The printer continues to work according to the GCode instructions, but the extruder stops extruding the filament and the model is missing its top part in one color. (Picture4) But the UltiMaker Cura slicer does not show any defect (Picture2). I solved my case with Geeeetech support, but I was advised to use a different slicer software, because according to them, UltiMaker Cura is not suitable for multi-color printing.

Can someone help me solve this error?

[MariMakes 178]

Hey @klickon,

 

Welcome to the UltiMaker Community 🎉
This looks like a problem with underextrusion. It almost seems like the flow of the layer doesn't start.
Have you considered adding a small block next to your primetower as long as your model to make sure that the primetower is longer and the material is primed? I've seen other people use that. 

[klickon 0]

Hi MariMakes,

 

First of all, thank you for welcoming me to the UltiMaker forum community. 

 

Your solution to the two-color printing problem I described occurred to me as well. I have already tried this procedure and it works. I just don't understand why it is not possible to implement this option directly in the software. For instance, the ability to choose the height of the primetower. The process described above increases the filament consumption and also increases the printing time. I tried printing several two-color 3D models and the result was always the same. The printer will no longer print the last layer in a different color.

[GregValiant 1,112]

@klickon post one of the "bad" gcode files.  Maybe something odd is going on at the last tool change.

 

The last change shouldn't be any different than the rest.  Same retraction and prime amounts as happened earlier in the print.