Click “Download This Thing!” then click the “comp_wheel.stl” file to download the STL file. For this example, we will be using blecheimer’s compressor wheel model for this tutorial. There are several popular websites that contain thousands of digital models that have already been optimized for extrusion-based 3D printing. Download from the internet: The first and the simplest method is to download a pre-existing STL file from the web. There are two common methods for obtaining an STL file:ġ.