How a part is oriented on the build platform affects strength, surface finish, accuracy, support requirements, and cost. Orientation is one of the most impactful decisions in 3D printing.
Key principles
Strength — Parts are weakest between layers (Z-axis). Orient so the primary load direction runs parallel to the layers, not perpendicular.
Surface quality — Upward-facing surfaces are smoothest. Downward-facing surfaces (in contact with supports) are roughest. Orient so cosmetic surfaces face up.
Supports — Minimize overhangs that require support material. Each support mark is a surface imperfection that needs cleanup.
Accuracy — XY dimensions (within a layer) are more accurate than Z dimensions (across layers). Orient critical dimensions in the XY plane.
Print time — Taller parts (more layers) take longer. Orienting a part on its side can significantly reduce print time and cost.
Orientation by application
Functional / structural parts: Orient so the layer lines run parallel to the expected load. A bracket that will be pulled downward should have layers running horizontally.
Visual / presentation models: Orient so the most visible surface faces upward (away from supports). Accept longer print time for better cosmetics.
Thin-walled parts: Orient vertically to avoid long unsupported spans. Horizontal thin walls sag without support.
Parts with holes: Vertical holes (along Z-axis) are more round and accurate. Horizontal holes may be slightly oval.
Technology-specific notes
FDM: Orientation matters most. Layer adhesion is the weakest point. Supports leave significant marks.
SLA: Orientation affects drain holes (for hollow parts) and support placement. Less strength anisotropy than FDM.
MJF: Orientation matters least. No supports needed. Parts are nearly isotropic. Still orient for surface quality on critical faces.
How to specify orientation
Include a note with your order specifying which surface is most important or how the part will be loaded. You can also include a screenshot showing your preferred orientation.
Or select “Tech’s Choice” and our engineers will optimize orientation for the best balance of strength, surface quality, and cost.
Makelab is a professional 3D printing service in Brooklyn, NYC. Our engineers review every file for printability and can help optimize your design. Get an instant quote.
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