Convert Dwg To Pat File

Converting a DWG (AutoCAD Drawing) file to a PAT (Hatch Pattern) file is not a native "Save As" function in AutoCAD. Because DWG files contain vector lines with specific coordinates and PAT files are text-based scripts describing line angles and offsets, the process requires a specific workflow or third-party tool.

Here is a detailed guide on the three best methods to achieve this, ranked from easiest to most technical. convert dwg to pat file

5. Sample PAT Code Generated from a DWG

If your DWG contained a simple brick pattern, the resulting PAT file would look like this: Converting a DWG (AutoCAD Drawing) file to a

*Brick_FromDWG, My converted brick pattern
; Generated from DWG geometry
0, 0,0, 0,4, 8,-8
90, 0,0, 8,8, 4,-4

5. One-Click PAT File Builder

• Auto-Formatting: Writes proper *pattern_name, description headers and correctly formatted angle, dx, dy, dash lists.
• Validation: Flags invalid PAT data (e.g., infinite loops, excessive dash lengths, unsupported arcs – converting arcs to short line segments automatically).
• Export Options:
  • Standard .pat file (ANSI)
  • .pat with embedded preview image
  • Copy-to-clipboard raw PAT definition

Method B — Use AutoCAD’s LINEWORK or Hatch creation tools

• Use AutoCAD’s “Hatch” or “Boundary” commands to create a hatch from the geometry, then use “-HATCH” and pattern editor utilities or third-party plug-ins that export/edit PAT files.
• Some CAD programs/plugins provide “create pattern from objects” or “export pattern” features — consult the plugin’s docs.

3. Critical Limitations & Troubleshooting

| Problem | Solution | | :--- | :--- | | Pattern is not seamless | Your DWG tile must be perfectly clipped to a rectangle. Use RECTANG + TRIM (Extend/Trim edges). | | Lines are 3D or curved | PAT files only support straight lines. Use FLATTEN (2D) and _DONUT (convert arcs to short line segments). | | File does not load in AutoCAD | PAT files must be plain text (Notepad), not Rich Text. Save as "All Files ." not .txt. | | Pattern scale is wrong | PAT defines tile size in drawing units. If tile is 10mm in DWG, it will be 10mm in PAT. No scale metadata. | select the lines

4. Best Alternative (If you cannot convert)

Instead of converting DWG→PAT, use DWG as a superhatch:

1. Create a small DWG file of your pattern (1 tile).
2. In a new drawing, type SUPERHATCH → Block.
3. Select your tile DWG.
4. AutoCAD tiles the DWG dynamically (no PAT file needed).

Error 4: My pattern doesn't repeat seamlessly.

Cause: Your selected geometry in the DWG was not perfectly tileable. Fix: In AutoCAD, use ARRAYRECT on your design. If the edges don't match, go back and move objects so that elements leaving the right edge enter the left edge exactly.

Method 1: Using Autodesk AutoCAD

1. Open your DWG file in AutoCAD.
2. Click on "File" > "Save As" and choose "PAT" as the file type.
3. In the "Save As" dialog box, select the PAT file format and choose the desired settings.
4. Click "Save" to convert the DWG file to PAT.

Method 3: Using Paid Plugins (Professional Workflows)

If you do this frequently, free scripts may crash on complex geometry. Professional plugins handle complex curves and dots much better.

• HatchKit: This is the industry standard software for editing and creating hatch patterns. You open your DWG/DXF in HatchKit, select the lines, and it generates a clean, optimized PAT code.
• AutoCAD Plugins: There are paid plugins available on the Autodesk App Store (like "Hatch Creation Tools") that add a button to your ribbon for one-click conversion.