Computational
Design

building sustainable digital workflows

Last updated: 18-10-2026

Department of Architecture · Aalto University

  4. 04Output07

    Preparing visual, printed, and fabricated output from the digital model.

    1. 04.01How to turn a 3D model into plans, sections and elevations?Upcoming
    2. 04.02How to make technical drawings clear and readable?Upcoming
    3. 04.03How to avoid colour and display errors when printing?
    4. 04.04How to fix blurry lines and pixelated PDF exports?
    5. 04.05How to choose the right settings for rendering?
    6. 04.06How to prepare a digital model for 3D printing?
    7. 04.07How to prepare a model for laser cutting?Upcoming
← Back to index
04 - OutputpublishedUpdated 18 Oct 2026

How to prepare a digital model for 3D printing?

How to prepare a digital model for 3D printing?

A 3D printer builds a real object layer by layer, so the model must describe something that could physically exist. This card uses the most common type, FDM (melted plastic), as the example: the object needs a closed volume, enough thickness and something to stand on.

A Closed Volume

The printer must know what is inside and outside, so the model has to be a closed solid. A single surface has no thickness and won't print: thicken it (OffsetSrf) and close every gap before export.

You may notice:

  • Roofs or walls modelled as single surfaces vanish in the print preview
  • The printer software says your model has holes

Search for

Tutorial

Scale & Minimum Thickness

Scaling a building down shrinks every part: at 1:200 a 20 cm wall becomes 1 mm, near a printer's limit. Fix the scale first, then thicken or drop details thinner than the printer's minimum wall.

You may notice:

  • Railings, mullions or thin walls are missing from the print
  • Fine details come out as blobs

Search for

Tutorial

Overhangs & Supports

FDM printers stack melted plastic layer by layer, so each layer needs something below it. Parts leaning out more than about 45° need supports, which leave marks — turn or split the model to avoid them.

You may notice:

  • Overhanging roofs or balconies print as stringy spaghetti
  • Support marks spoil the surfaces you wanted to show

Search for

Tutorial

From Model to Slicer

Printers read meshes, not NURBS: STL works everywhere but stores no units, 3MF keeps units and colours. A slicer then cuts the mesh into layers and print paths — ask your workshop for its settings.

You may notice:

  • Your model arrives in the slicer 1000× too small or too big
  • Curved parts print with visible flat facets

Search for

Tutorial