MatterControl’s new hexagon infill is designed to be both strong and light, achieving the defining quality of hexagonal patterns. The reason hexagonal patterns are prevalent in nature is due to their efficiency. In a hexagonal pattern, every line is as short as it can possibly be. Because of this, a large area can be filled with the fewest possible number of lines. For example, in a beehive, honeycombs require the minimum amount of wax to construct while providing the necessary functional strength.

Geometry of a Hexagon

The most important quality of hexagons, and why they appear so frequently in nature, is that they achieve the best balance of strength and material use. Specifically, they use the least material per volume filled than any other pattern. More strength can be achieved by using a triangle infill but it also uses more material in the same amount of space.

Until now, implementations of hexagon infill for 3D printing have focused on their aesthetic value rather than strength.

Below is an example of the hexagon infill that has most commonly been used up to this point. You can see that it is actually doubling every third line and using much more material than is necessary.

In order to ensure that our hexagon patterns are strong, we needed to make a number of considerations specific to 3D printing:

• Print the longest connected lines possible to create continuous lines.
• Print each successive layer at different angle directions to give strength in all directions.
• Optimize movements as much as possible to decrease print times.

Hexagon Continuous Line Printing

Below is an example of how successive layers are printed. Each layer is printed with a different bias direction to ensure strength. These pictures only show the major connecting lines, the shorter connecting lines are printed opportunistically after ensuring these first strength lines are printed.

Hexagon Infill Directions

Here is a 3D layer view of the completed hexagon printing. You can see that the minimum amount of material has been used for all layers.

Hexagon Infill Pattern

Hexagonal infill provides the best strength:material ratio. The strongest possible infill, however, is triangles, and MatterControl does a great job of creating an efficient, effective triangle pattern.

Triangle Infill Pattern

Grid is another very common infill pattern. While strong, it is preferable to triangle infill only when it brings a specific aesthetic to your print.

Grid Infill Pattern

Lines infill is mostly a legacy infill. It alternates between line direction on each subsequent layer. The main advantage of this infill type is that while extruding it never directly crosses a previously extruded line on the same layer. This can help when printing very thick layers or if you see your head bouncing on line crossings.

Lines Infill Pattern

The final infill pattern that MatterControl’s native slicing engine provides is concentric. This pattern can be used to reduce internal tension on complex parts with many small or curved internal sections. This sometimes reduces warping, but the pattern needs to be at a high density to provide sufficient strength for most parts.

Concentric Infill Pattern

Triangles provide the highest strength infill option for 3D printing, but maximum strength isn't always needed. Grid, lines, and concentric patterns can fill specific aesthetic or other needs, but aren't always the best option for rigidity.

MatterControl's new hexagon infill offers high strength and efficiency as well as a pleasing aesthetic. Consider it for your next 3D printing job.

Happy Printing!