Two color print with dual extruders and only one model file?

[jazzychad 1]

Let's say I have been given an STL model to print (i.e. I am not the designer of the model and don't have access to the original design files). This model is supposed to be printed in two colors, and the instructions say to do a filament change at a certain height.

 

I know I can do an actual filament change (using the post-processing plugins), but since I have an Ultimaker 3 with dual extruders, I am trying to figure out if it is possible to use Cura to slice the model such that it uses one print core for the first X layers, and then uses the other print core for the remaining layers? Yes, usually for dual extrusion you have two models and merge them together, but in this case I only have one model file and the color change is completely in the vertical direction.

I have tried doing various things with duplicating the model and using support blockers to "selectively" print part of the model for each print core, but that doesn't seem to work (unless there is a way to do this I haven't discovered).

Is there any way to do this?

[jazzychad 1]

To give the concrete example, I have a piano keyboard model. I tried multiplying the model, then adding a support blocker as a cut mesh to each instance which would prevent the "wrong" portion of the model from being printed in that color. So far so good, but if I try to merge or overlap the models to align the keys, the support blockers of each overlap the other model and everything cancels out, leaving nothing to be printed!

[tinkergnome 927]

I think it is not necessary to duplicate the model. Simply select a different extruder for the cutting mesh (in addition to any other setting of you like) and you're done.

 

Like in the following instructions:

 

Quote

 

"In the example below, we print the 3D model with extruder 1 and its print settings. We print the modifier mesh with extruder 2 and all its print settings. This allows adjusting the print profile per extruder which will be reflected in the 3D print."

 

 

https://support.ultimaker.com/hc/en-us/articles/360013370140-How-to-adjust-print-settings-of-a-part-of-my-model-in-Ultimaker-Cura

 

[jazzychad 1]

8 hours ago, tinkergnome said:

I think it is not necessary to duplicate the model. Simply select a different extruder for the cutting mesh (in addition to any other setting of you like) and you're done.

 

Wow, magic. This works!! I was waaay overcomplicating it. Thank you!

Next issue is, seems like the prime tower is printing black (and white) on all the white-only layers all the way up, which seems unnecessary... I guess the prime tower isn't strictly necessary in this particular case, but is there a way to improve it?

 

[smedway 0]

On 1/15/2021 at 2:51 AM, jazzychad said:

Did you figure out how to do this? Because the instructions on the page the link leads to don't actually explain how to create two color models... just that there are settings you can customize. What did you change and how do you actually get it to print in two colors?