PAT files only support lines. If your DWG has polylines, circles, or arcs, explode them or approximate them with short line segments.
For decades, the CAD community has relied on custom LISP routines.
Use these with caution. Hatch patterns require strict "tiling" logic. Most automated online converters struggle to recognize where a pattern should repeat, often resulting in "broken" hatches. Step-by-Step: How to Prepare Your DWG for Conversion dwg to pat converter
In this guide, we’ll explore why this conversion is so tricky, the best tools available for the job, and a step-by-step approach to getting it right. What are DWG and PAT Files?
If your DWG geometry is too large or too small relative to the 1-unit export limit, the pattern will appear solid or empty. Conclusion PAT files only support lines
If your converted hatch looks like a mess of "spaghetti" lines, it’s usually due to one of three things:
The native format for AutoCAD. It contains complex vector data, layers, blocks, and 3D geometry. Use these with caution
The PAT format has a limit on how many lines it can process in one "cell."