20×20 mm Reference Calibration Square

A simple but clever 20×20 mm square used as a reference object for scaling models when converting images or drawings into STL files.How it works:Print this 20×20 mm square.Place it alongside the object you want to convert into a 3D model (via photo or drawing).Import the image into your CAD software (Tinkercad, Fusion, Blender, etc.).Draw a matching 20×20 mm square in the software.Scale the imported picture until both squares match in size.This ensures accurate scaling of any hand-drawn or photo-based model without needing a 3D scanner.Simple design, but very effective!