Make various fill patterns

Slic3r is considered one of the best slicing software for 3D printing. Many features and widely used slicing procedures have been presented there for the first time. Among other things, they presented for a first time a pattern (3D honeycomb infill) that can be varied across the layers in three dimensions. Slic3r not only offers a large variety of patterns (Fig. 1), but also it gives the possibility to create your own.



Figure 1. Infill patterns at varying densities. Left to Right: 20%,40%,60%,80%.  (Source: Link).


Procedure: Coping a pattern (test)

A comparison will take place between the actual Concentric pattern offered by the Slic3r and the same pattern designed in a CAD software. The goal is to produce the same result. Therefore, the pattern Concentric with 50% infill density and without top or bottom layers was designed and was exported as STL (Fig. 2).


Figure 2.The designed Concentric pattern with 50% infill density.

A small cube (20X20X20 mm) will be tested using the Slic3r pattern and the designed pattern. By clicking on settings, Slic3r offers you an option to load a modifier (Fig 3.). The Concentric pattern as an STL was loaded (Fig. 4).


Figure 3. A cube (20X20X20 mm) and the ‘Settings’ option.

Figure 4. Loading Concentric pattern.

The main idea is that the loaded pattern should have 100% infill density, perimeters, top and bottom layers and in the general settings, these values should be zero (Fig. 5, 6a & 6b).

Figure 5. Modifier settings: 100% infill density, 3 Bottom and top solid layers, 3 perimeters.

Figure 6a. Print settings: 0 Bottom and top solid layers, 0 perimeters.

Figure 6b. Print settings: 0% fill density.

By exporting the gcode and clicking preview we can see the results (Fig. 7) and compare it by using the Concentric pattern of the Slic3r software (Fig. 8). Both of the gcode produce the same result.


Figure 7. The result of using the modifier to create our own pattern.

Figure 8. The Concentric pattern of the Slic3r software.

It has to be mentioned that using the same procedure but with exactly the opposite settings, the inverse pattern can be created (Fig. 9).

Figure 9. The inverse pattern of the Concentric designed pattern.

If you have a real object that you want to print using your own pattern, you have to repeat the pattern design and exported as an STL with the same volume of your object. The advantage of this technique is that you don’t need to use a Boolean difference to create a new STL. Also in most of the cases using a Boolean difference, the merged STL cannot complete and the relative software can fail (sometimes there are small holes). You have to experiment with the setting and find the proper result for your project. For example, in Figure 10 and 11 you can see the implementation of a different pattern and the result.

Figure 10. The design of the new pattern.


Figure 11. The results of the new pattern.

Procedure: Applying our pattern to a model

We want to print the bunny model (Fig. 12) with the designed pattern (Fig. 13).

Figure 12. The original model.

Figure 13. The pattern designed enough to fit the model.

As it was described earlier, clicking settings and loading the pattern STL as a modifier we can merge the pattern structure with the object (Fig. 14). The settings for the modifier are presented in Figure 15.

Figure 14. Loading the modifier.

Figure 15. Settings for the modifier.

At this time we want perimeter for the model. Therefore, we will use a 3 lines perimeter in the model but the rest of the settings will be equal to zero (Fig. 16a & 16b).

Figure 16. Print settings: 0 Bottom and top solid layers, 3 perimeters.

Figure 16b. Print settings: 0% fill density.

The results are presented in Figure 17 and 18

Figure 17. The bunny model in a preview.

Figure 18. A cut of the bunny model with the embedded pattern.