Which infill is best for 3D printing? Well, there is no definitive answer as it depends on the use case. But, if you want to print 100% infill PrusaSlicer will automatically default to Rectilinear infill regardless of what option you have selected. In order to determine what is the best infill pattern ask yourself some questions:
- Does it need to handle stress? If you are printing a frame or handle, or something small you keep in your pocket then you will want to print with high strength and/or high density infill. If you are printing a simple housing or replacement part, though it’s subjective, you may get away with printing something light and save on time and material.
- What is the most common infill pattern? There is no good answer for this. Instead ask yourself, how much stress does your print need to handle?
- Generic models and figurines – use low strength
- Standard prints subjected to low stress – use medium strength
- Functional prints subjected to high stress – use high density or high strength infill
- Flexible objects – use infill patterns with no intersection points
- Is it better to have use a mesh or solid type infill pattern? Mesh prints produce a lighter print which gets away with printing with gaps between layers, whereas solid prints creating intersecting points where material accumulates. This makes the print stronger, but also could risk failure with the nozzle.
- Does it need to handle weight or load? And, how much? While casing may generally not need to handle weight, if you know the print may need to handle some abuse or load, sometime even the simplest of things will get banged up.
- Do you want to fill the 3d printed object with liquid? Maybe you want to add water in a printed vase or maybe you want to increase the weight and stability without using as much filament.
- Does the print need to be flexible or rubbery? Such as a tire, shoe insole, phone case, etc…
- Should you print with more or less density? This answer to this is also subjective depending on how much time and material you want to use as well as how durable the print needs to be to be lasting and functional. For low density use 20%, for high density use 80%.
Aside from all these questions to determine which infill you should use this article describes the characteristics , benefit/purpose, and best used for.
Low Strength Infill Patterns:
– Rectilinear Infill
– Aligned Rectilinear Infill
Medium Strength Infill Patterns:
– Grid Infill
– Triangles Infill
– Stars (Tri-Hexagons) Infill
High Strength Infill Patterns:
– Gyroid Infill
– Honeycomb Infill
– 3D Honeycomb Infill
– Cubic Infill
– Support Cubic Infill
– Adaptive Cubic Infill
Flexible Infill Patterns:
– Concentric Infill
– Archimedean Chord Infill
Just For Looks Infill Patterns:
– Lines Infill
– Hilbert Curve Infill
– Octagram Spiral Infill
Low Strength Infill Patterns
The Rectilinear infill pattern has each layer printed in one direction. Every next layer prints 90° from the previous layer, and therefore does not print on every line. Whereas the grid infill pattern prints on every line in every layer. Rectilinear is a mesh where grid is solid.
Since the Rectilinear infill pattern does not prints in one direction on each layer this saves on filament material and does not accumulate material at intersections such as the grid pattern will.
When 100% infill is desired use Rectilinear infill. If a different infill pattern is selected with 100% infill PrusaSlicer will automatically switch to the recilinear infill pattern.
*Note: In Cura, this pattern is known as Lines. Another similar pattern in Cura is Zig-Zag, however the difference with Zig-Zag is the line is printed as one continuous flow and the only noticeable difference is along the edges.
Aligned Rectilinear Infill
The only difference from the standard Rectilinear infill pattern is that the printer prints straight lines parallel to each other.
The Aligned Rectilinear infill pattern is a mesh as oppose to a solid thus saving on material. This pattern does not accumulate material at intersections.
Be cautious of low infill density and bridging as the top layer might droop between lines.
Medium Strength Infill Patterns
Grid prints on every layer. Rectilinear does not. Grid is solid whereas rectilinear is a mesh.
Since Grid infill is more solid than rectilinear there is better layer adhesion. Material accumulates at intersection points for improved strength.
Keep an eye on the print job in case the nozzle jams or print fails since this print pattern purposefully accumulates more material at intersections points.
The Triangles infill pattern prints solid, and like the grid pattern, creates numerous intersection points. This infill pattern prints as a solid rather than a mesh.
Another common pattern for high strength. Failure from bridging is not likely to happen compared to the grid pattern. This pattern prints less time and material than the cubic pattern. Intersection points help with strength as material accumulates at intersections.
When heavy load strength is desired the Triangles infill pattern is most recommended.
Stars (Tri-Hexagons) Infill
The Stars infill pattern contains of both hexagon and small triangles producing a star-like shape. This infill pattern prints as a solid rather than a mesh.
Hexagons have shorter lines compared to the Grid infill thus minimizing the risk of bowing. Like the Grid and Triangles infill patterns intersection points accumulate material which also helps with strength.
When heavy load strength, infill with shorter line spans, and reduced risk of bowing is desired the Stars infill pattern is recommended.
High Strength Infill Patterns
The Gyroid infill pattern is esthetically pleasing and has great strength ratio in all directions.
Gyroid infill provide great support for every direction. This infill pattern prints relatively fast and saves on material. There are no intersection points where the material accumulates.
This pattern is the best choice when filling with resin or other liquid is desired.
The Honeycomb infill pattern is made up of hexagons meshed together.
The main benefit of the Honeycomb infill pattern is to provide mechanical resistance without the accumulating material at intersection points like the grid pattern does. However, more time and material is used as some edges of the honeycomb pattern do not overlap.
The Honeycomb infill is used when a semi-fast print with moderate strength is desired.
3D Honeycomb Infill
The 3D Honeycomb infill pattern with octagons and small squares providing different thicknesses throughout the print pattern. Due to how the material is layered with gaps between layers this infill pattern creates more of a mesh.
3D Honeycomb infill provides greater overall strength in every direction than a rectangular pattern.
When higher strength than the Grid pattern is desired the 3D Honeycomb infill pattern is more commonly used.
The Cubic infill pattern prints solid thus printing many intersection points on each layer. However, each line is printed at a slight angle creating a cube orientation.
The Cubic pattern creates numerous air pockets which enables the printed object to float on water.
If the purpose is to print with high strength and give the ability to float on water then we suggest using waterproof filaments such as PETG.
Support Cubic Infill
Support Cubic infill and Adaptive Cubic infill is essentially the same pattern, however the support cubic infill increases in density only in the Z-axis.
The Support Cubic infill pattern main purpose is to provide more support for the top layers while saving as much time and material as possible.
When the ideal situation is to provide stronger support at the top layer, print faster, and save on material use the Support Cubic infill.
*Note: In Cura, other similar patterns are the Octet and Quarter Cubic only that the shapes look like squares instead of triangles and lines patterns appear like double lines. The differences are that the Octet prints double lines in both directions and Quarter Cubic only prints double lines on one direction.
Adaptive Cubic Infill
Both Adaptive and Support Cubic infill patterns initially look identical, however the difference is where the increase in material density is focused. Adaptive can be set to get more or less dense from center of mass to parameter of model.
This infill pattern will print out a denser patterns at the top, bottom, and all sides to save on material and yet provide strength to the overall print.
When making large prints with a big internal area adaptive Cubic infill is the best option to save on time and material.
*Note: In Cura, this pattern is known as Cubic (Subdivision.
Flexible Infill Patterns
The Concentric infill pattern copies the perimeter of the print object offsetting the pattern getting smaller toward the center of the object. Print time can vary depending on complexity of shape.
This infill pattern is best used for flexible parts or transparent prints.
When flexibility is desired the Concentric infill pattern is most commonly used.
Archimedean Chord Infill
The Archimedean Chord infill provides a medium strength spiral therefore there are no intersecting points.
This spiral infill print makes it easier for the nozzle to travel and saves on time and material compared to most other infill patterns.
When flexibility is desired with flexible filament material use the Archimedean Chord. This infill pattern can also be used for filling with liquid.
Just For Looks Infill Patterns
The Lines infill pattern prints lines at a slight angle as oppose to parallel lines, however there are no intersecting points. Thus, this infill is prints gaps between layers creating a mesh. Print time and material consumption is very similar to the Rectilinear infill.
Like the Rectilinear infill the line infill is a low strength mesh print that is just for looks and is one of the faster print patterns.
When printing does not require a lot of strength and you want to print fast the Line infill pattern is one of the best.
Hilbert Curve Infill
The Hilbert Curve infill pattern produces a rectangular maze-like look. This is a medium strength pattern that takes a little longer to print.
This is mainly just for looks but with the large cavities it is also good for filing with liquid.
When a non-traditional look is desired and/or need to fill with resin or liquid the Hilbert Curve is a great option.
Octagram Spiral Infill
The Octagram Spiral infill pattern is a star-like, but spiral infill. Consumption of material is similar to the archimdean chord, but prints longer due to all the angles.
This pattern can be used for medium strength, flexibility, and aesthetics.
When printing for looks, filling of liquid, and or some flexibility is desired the Octagram spiral infill is a nice pattern to use.
After taking a deep dive I have come to the conclusion for the most common infill I would use depends on my print job. If I were to print one or two small items I would choose 80-100% density rectilinear infill and if I were to make a much larger print I would go with Adaptive Cubic to save on time and filament material while retaining the integrity of the model.
If I were to make a print with very light infill I would avoid using the grid pattern to avoid the chance of bowing. If my focus is to handle load I would choose an a solid infill rather than a mesh. Another aspect to keep in mind is the CAD model design. To learn more about this check out our CAD Modeling Errors You Need to Fix Before 3D Printing.