Watching a 3D printer at work never gets boring. “Why did he turn right here instead of left? Why does he fill in this area first and not go over it?” The exact answer to these questions is disappointingly trivial: the 3D printer makes this exact movement because it just stubbornly executes G-code, and the programming language instructions tell it to do just that. The fascinating thing about it, the sophisticated strategy behind the movements was previously generated by an algorithm in software, the slicer.
Before printing on the PC, you load a 3D model into the slicer as an STL or 3MF file. The files only show the shape of the model, but do not have instructions for the printer. The slicer cuts the model into slices that are as high as the printing layer and then develops a strategy for each slice as to how the nozzle of the FDM printer (FDM stands for Fused Deposition Modeling, i.e. 3D printing with precisely melted plastic threads (filaments) should move, so at the end a print that is as stable, dimensionally accurate and flawless as possible is created.Slicers are therefore the intelligence behind 3D printing and are primarily responsible for the success of the prints.
All important slicers are open source software that can be used free of charge and can be configured extensively (for a test also with proprietary slicers in the test field). Because of the many settings they offer, they seem dauntingly complex for beginners. Objects that look the same on the outside can also be printed particularly easily, quickly or particularly stably via slicer settings.