gMax 2 PRO Dual 2in1 - Topographic Model 3D Print


The gMax 2 PRO Dual 2in1 is a dual extruder with two inputs and a single output. This makes leveling the hotend and printing dual colors much easier. The hotend will print a single color with extruder 1 then retract the filament out of the way so the second color can be used. Combined with some of PrusaSlicers advanced features and the result is an easy dual color printing with impressive results.


In this article we will go over 3d terrain generation, dual 2in1 slicing settings, using PrusaSlicer extruder sequences to create a unique 3d topographic map and printing on the gMax 2 PRO Dual 2in1 extruder.




Where to Start? How About a Model


We used this very useful online 3d terrain generator to create a topographic map. Just select your region and export the model.

A Topographic map image of Lake George NY
Topographic map of Lake George, NY


Touch terrain can be found here:

https://touchterrain.geol.iastate.edu/



In our case we selected a region of Lake George in upstate New York which is especially beautiful in the summer.


You can download the model here:

gcreate_scaled model_2in1 article
.zip
Download ZIP • 6.44MB






Lets Setup the Slicing Settings


For this print we will be using PrusaSlicer 2.3 since it has a few very useful features that

work with the 2in1.

Select gMax 2 PRO Dual 2in1 Profiles

Open PrusaSlicer and make sure you have the gMax 2 dual 2in1 profile selected.



You can find the gMax configuration files here:

http://forum.gcreate.com/index.php?resources/categories/prusaslicer.25/


Once the printer is selected you should see a purge tower appear on the model. You can drag this out of the way if its too close. Just drag with the left mouse button.


Most of the default settings will work and we may just have to change the infill and select our layer height.


Suggested settings:

  • Layer Height: 0.2mm

  • Infill: 15%

  • Top Solid Layers: 4

  • Bottom Solid Layers: 3

  • Speed: 60m/sec



Option #1 (No Sparse Layers)

Experimental Feature - No Sparse Layers

PrusaSlicer also has a very useful setting which will drastically reduce the purge tower on certain models. Enable "Print Settings > Multiple Extruders > No sparse layers (EXPERIMENTAL)".




No sparse layers will only purge the nozzle when it needs to change color. The printer will print all the layers of color 1 and when it's ready for a color change it will move to the purge tower and lower to the correct height (from the last color change).


Once purging is complete the nozzle will raise back up and resume printing on the model. This reduces all the extra layers of the same color that aren't required in the purge block.

Move the purge tower out of the way

You MUST make sure the purge tower is far enough from the print so the extruder will not collide when it lowers. We recommend putting it in the left rear corner.











Option #2 (Purge in Infill)


Another option to reduce purging waste is to have the printer purge in the objects infill or on a sacrificial object.


Next to the model name you can see a small gear icon. Click on that gear then select "Wipe options".


Enable "Wipe into this object's infill"










When purging in an objects infill it's possible to have slight color bleeding so this option must be used only in certain situations. Additionally, if the infill is too small in some areas, a purge tower will also be generated for the remaining filament to be purged.





Time to Slice


For this article we're going with Option #1 for purging so we will have a purge tower in the left rear of the bed.


Once the model is loaded and everything is set up go ahead and slice the model.


The slicing result, but where's the purge tower?




What About The Topographic Lines? The Second Color?

This is where the magic happens! Set extruder sequence

When slicing is complete, that's where the magic comes in! Initially the model will consist of all one color but we want every 10th layer to switch to the second color. PrusaSlicer has a useful built in script that will process the model after slicing is complete.


In the bottom right of the slicing window you will see a gear icon. Click the gear and select "Set extruder sequence for the entire print".



We want (9) layers of color #1 and (1) layer of color #2. This will then repeat until the full height is achieved.



Click the plus icon to add a new extruder until you have all 10. You can play with different arrangements to get your desired effect.












Once you're finished click OK and the model will process. With "No Sparse Layers" turned on, you will see how much lower the purge tower is. (Note you may have to re-slice the model for the script to work).