What Is Infill in 3D Printing

Why It Matters

When it comes to 3D printing, infill plays a critical role in determining the strength, weight, cost, and print time of your object. Whether you’re printing a functional prototype or a decorative model, understanding infill can help you make smarter design and material choices. At BritForge 3D, we optimise every print to meet your needs and infill is a key part of that process.

What Is Infill?

Infill refers to the internal structure of a 3D printed object. Instead of printing a solid block, most parts are printed with an internal pattern that gives them strength while saving material. The outer shell (or perimeter) is printed solid, while the inside is partially hollow filled with a repeating pattern called infill.

Why Infill Matters

  • Strength: More infill = stronger part
  • Weight: Less infill = lighter part
  • Print Time: Higher infill increases time and cost
  • Purpose: Match infill to function (display vs. functional)

Common Infill Patterns

  • Grid: Balanced strength and speed. Good for most parts.
  • Gyroid: Excellent strength in all directions and efficient material use.
  • Honeycomb: Lightweight with moderate strength. Popular for visual appeal.
  • Lines: Fastest to print, used for basic prototypes.

Recommended Infill Percentages

Use CaseInfill PercentageNotes
Display Model10–15%Light and fast to print
Functional Part25–50%Stronger, better durability
Structural Load-Bearing50–100%Max strength, longer print time

How Infill Affects Cost

Higher infill means more material and longer print times which increases the cost. For example, changing from 15% to 50% infill might double the amount of filament used. At BritForge 3D, we help you choose the best balance of strength and budget for your application.

Infill Tips

  • Use low infill for decorative or non-functional models
  • Choose gyroid or grid for strength and reliability
  • Keep in mind that more infill doesn’t always equal better results
  • Use multiple perimeters instead of just increasing infill

How BritForge 3D Optimises Infill

We analyse every print job to recommend an ideal infill percentage and pattern based on use, strength, and cost. Whether you’re printing a bracket, toy, or prototype, we tailor each print to perform as needed saving you time and money.

Conclusion

Infill is more than just a setting it’s the backbone of your 3D printed part. Understanding how it works helps you make better decisions, whether you’re designing a prototype or ordering your first custom part. Let BritForge 3D help you find the perfect infill for your next project.

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