: PAT files have line limits. Simplify your DXF geometry by removing unnecessary segments or tiny details that won't be visible at scale. Check Your Units
If you choose to manually edit or create a PAT file, it must follow a specific ASCII syntax: Tekla User Assistance Block to PAT — AutoCAD Pattern Conversion #AutoCAD #Tips
Note the folder directory listed (or add a custom folder) and paste your .pat file into that directory.
A robust standalone utility widely used by CAD managers for batch conversions and precise pattern generation.