If you simply want to use a drawing as a pattern within your current project without creating a separate .pat file, use the command. This is part of the AutoCAD Express Tools . Step 1: Draw the geometry you want for your pattern.
If your DWG already contains a hatch pattern and you need to "extract" it into a .pat file for use in other drawings, you can use specialized LISP utilities. convert dwg to pat file
For creating a true, portable hatch definition from scratch, third-party generators are often the most reliable way to handle complex geometry. SAVING AUTOCAD DWG AS .PAT FILE - Forums, Autodesk If you simply want to use a drawing
Run the command (e.g., GETPAT ) and select the hatch in your drawing. If your DWG already contains a hatch pattern
These are popular free LISP utilities available on platforms like CAD Forum . How to use: