How 3D Printing Works
How does FDM 3D printing work? Step-by-step guide from digital file to finished part. Learn about modeling, slicing and finishing.
3D printing, also known as additive manufacturing, is a technology that creates three-dimensional objects from a digital model. In this guide, we explain step by step how FDM (Fused Deposition Modeling) 3D printing works, the most popular technology and the one we use at Douro Make.
What is 3D printing?
3D printing is a manufacturing process that builds objects layer by layer. Unlike traditional methods that remove material (such as milling or cutting), 3D printing adds material only where needed, reducing waste and enabling complex shapes impossible with other techniques.
From digital file to physical part
The process starts with a digital 3D model, created in CAD software or downloaded from online repositories. This file (usually in STL, OBJ or 3MF format) is processed by slicing software that divides it into hundreds or thousands of thin layers and generates instructions for the printer.
The FDM process step by step
Model preparation — The 3D file is imported into the slicing software, where parameters like layer height, infill, supports and material are defined.
Heating — The printer nozzle heats up to the ideal filament temperature (180°C to 260°C, depending on the material).
Extrusion — The filament is pushed through the heated nozzle, which melts it and deposits it on the print platform following the programmed path.
Layer-by-layer construction — After completing a layer, the platform lowers (or the nozzle rises) and the next layer begins. This process repeats until the part is complete.
Post-processing — After printing, supports are removed (if any), surfaces are sanded and finishes are applied as needed.
What is 3D printing used for?
3D printing has applications in virtually every sector: rapid prototyping for design validation, manufacturing functional replacement parts, custom gifts, decorations, corporate gifts, architectural models, custom tools, and much more.