Prusa may very well make the best 3D printers on the market. They are well known for their high quality in parts and production. The slicer they offer is no exception. A Slicer is the software used to convert your 3D design into "g-code' that a 3D Printer can interpret to know how to create the design in the material you are using (height, width, temperature speed, etc.).
PrusaSlicer is a free and Open Source, cross-platform application for 3D printing. It supports the slicing of STL, OBJ, and AMF files and provides support for customizing your slicing settings. Prusa Slicer also offers an advanced mode for expert users who need more control over their slicing settings. PrusaSlicer currently supports 150+ filaments and resins with built-in presets.
PrusaSlicer is based on Slic3r and reworked to make menuing easier with a much easier, clean UI. Further, PusaSlicer offers some very unique features like "paint Custom Supports" that allow you to simply draw where you would like (or not like) support and 'Paint On-Seam' which enables you to tell the software to smooth out the seam on a print with its internal algorithm. PrusaSlicer also supports changing filament mid-print for color change and multi-material printing.
Amongst other updates and bug fixes, PrusaSlicer 2.5.0+ now imports STEP format 3D models, which means you can drop a CAD format(.stp or .step) 3D model directly into a slicer.
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