These STL files were derived from 2D plans for a Dutch Series SIK 300 shunter engine by designer Julian De Waal and I have included a PDF of the 2D drawings for reference. Many of the 3D parts were designed to avoid the use of support and minimize printing times by keeping parts short in the z-axis. I recommend printing the parts in PLA and assembling the parts with Testors Cement for Plastic Models (in the red tube). The parts are scaled directly from the source 2D drawings and will need to be scaled down to fit most 3D printers. I recommend 18% scale as that will build a nice coffee table model just over 9" long. I like to select the color of the PLA filament for each part or set of parts to fit the color scheme of the final model to avoid painting.