Optimization Guide

Design for 3D Printing

Maximize quality and minimize cost by optimizing your CAD models for FDM manufacturing. Follow these core principles to ensure your parts come out perfect every time.

Wall Thickness

Avoid paper-thin walls. 3D prints are built in layers; walls need enough perimeters to be structural.

Minimum0.8 mm
Recommended1.2 mm - 2.0 mm
Structural3.0 mm+

Overhangs & Supports

The 45-degree rule: Angles greater than 45° usually require support structures, which can affect surface finish.

Self-Supporting< 45°
Requires Support> 45°
Max Bridge10 mm

Holes & Tolerances

Designing for fit: Don't design parts with exact same dimensions if they need to assemble.

Tight Fit0.1 mm gap
Standard Fit0.2 mm gap
Loose Fit0.4 mm gap

Orientation & Strength

Parts are weakest along the Z-axis (layer lines). Orient your part so loads don't pull layers apart.

X/Y StrengthMaximum
Z StrengthReduced
DetailTop surfaces

Understanding Anisotropy

Unlike injection molded parts, 3D prints are anisotropic, meaning their strength varies depending on the direction of the load. The bond between layers is always weaker than the plastic itself.

Horizontal Printing

Best for tensile strength along the length of the part.

Vertical Printing

Avoid for tall, thin parts that will experience side loads.

Visualizing layer-line stress distribution

15%
40%
100%

Infill vs. Shells

Strength comes from shells (walls), not infill. Increasing wall count is more effective than increasing infill percentage for most mechanical parts.

  • 15-20% Infill: Standard for most parts.
  • 40-60% Infill: Heavy duty functional parts.
  • 4+ Shells: Recommended for threaded inserts or high-stress areas.
Pre-Upload Checklist

Manifold Geometry

Ensure your model is 'watertight' with no missing faces or open edges.

Scale & Units

Export your STL in Millimeters (mm) to avoid scaling issues.

Wall Thickness

Check that no part of your model is thinner than 0.8mm.

Assembly Gaps

Add at least 0.2mm of clearance between moving or interlocking parts.

Flat Base

Ensure your model has a flat surface to sit on the print bed.

File Size

Keep files under 128MB for the fastest processing.

Ready to print?

Now that your model is optimized, get an instant quote and start production.