• How to make a 3d model for 3d printing 
  1. Define the project 
  2. Choose the right CAD program 
  3. Creating the model 
     • Sketch the basic shape 
     • Build up the geometry 
     • Ensure printability 
  4. Exporting the model 
  5. Prepare for printing 
  6. Test and iterate 
     • Tips for a smoother workflow 

How to make a 3D model for 3d printing 

Creating a 3D model for 3D printing involves several steps from idea to a finished digital model that can be printed. The process requires understanding design principles, using computer-aided design (CAD) software and preparing for printing. Here is a step-by-step guide: 

Define the project 

Before you start creating a model, it is important to clarify its purpose and requirements: 

• Function: Should the model be functional, aesthetic or both? 

• material: Choose a material (e.g. PLA, ABS, PETG) based on the needs of the project. The material affects the strength, flexibility and detail of the design. 

• Printing technology: FDM, SLA and SLS have different requirements for details and geometry. 

Choose the right CAD program 

A CAD program is used to create a 3D model. Choose a program that suits your level of experience and the complexity of the project: 

• For beginnersTinkercad (web-based and easy to use). 

• For advanced usersFusion 360 or SolidWorks (more functional with tools for mechanical and technical details). 

• For artistic models: Blender or ZBrush. 

Creating the model 

Use the CAD program to create a model according to the following steps: 

Sketch the basic shape 

Start with a simple 2D sketch of the basic shape of the model. Most CAD programs offer tools for drawing lines, circles and other shapes that can be extruded into 3D. 

Build up the geometry 

Extrude, cut away or shape the model to achieve the right design. CAD programs have various functions for working with details such as holes, edges and surfaces. 

Ensure printability 

For 3D printing, some design rules are important: 

• Wall thickness: Have sufficiently thick walls for strength (at least 1-2 mm depending on the material). 

• Avoid overhangs: Minimize parts with overhangs over 45 degrees to avoid support materials. 

• Enclosed surfaces: The model should be ”watertight”, i.e. without open holes in the geometry. 

Exporting the model 

Once the model is complete, it needs to be saved in a format that 3D printers can read, usually STL or OBJ: 

• STL: Most common and used to describe the surface of the object with triangles. 

• OBJ: Contains both geometric data and textures (for multi-color printing). 

Check that the file is free of errors using tools such as Netfabb or Meshmixer. 

Prepare for printing 

Before printing, the model is loaded into a slicer software (e.g. Cura or PrusaSlicer): 

• Set parameters: Select material, layer height, infill and support material if necessary. 

• Generate G-code: The slicer converts your STL file into G-code that the printer can use. 

Test and iterate 

The prototype may require adjustments based on: 

• Fit or dimensions. 

• Stability and strength. 

• Appearance. 

Update the design and test until the model meets your requirements. 

Tips for a smoother workflow 

• Use templates: If possible, start with an existing 3D model and adapt it. 

• Verify tolerances: For moving parts or joining, it is important to include the right clearance in the design. 

• Check cost: The RPS online platform can help you quickly calculate material costs and adjust the design accordingly. 

With these steps, you can efficiently create a model ready for 3D printing, adapted to your needs and the printer technology.