*weaver_terrazzo, Terrazzo pattern from DWG file
; Generated by Dynamic Pattern Weaver v1.0
; Tile size: 12.00x12.00 units
45, 0,0, 0,12, 6,-6
Converting a standard DWG drawing into a custom AutoCAD hatch pattern (.PAT file) is a common challenge for CAD designers who need unique textures that aren't included in the default library. While AutoCAD doesn't have a single "Save As .PAT" button, you can achieve this by preparing your geometry and using external conversion tools or specialized Express Tools. Understanding the Conversion Process
A .PAT file is essentially a text-based set of coordinates and instructions that tell AutoCAD how to repeat lines to form a pattern. Because hatch patterns are mathematical repetitions, they can only be created from simple linear geometry. 1. Prepare Your Geometry
Before converting, you must ensure your drawing meets the technical requirements for a hatch pattern:
Use Only Lines: Hatch patterns only support straight segments. Convert all arcs, circles, or splines into small line segments.
Explode Blocks: If your pattern is currently a block, use the EXPLODE command to reduce it to basic geometry.
Simplify the Design: Keep the pattern tile as small and simple as possible to prevent slow performance in AutoCAD.
Position Near Origin: Move your pattern tile so that its base point is at or near (0,0,0). This prevents alignment issues during the tiling process. Methods for Converting DWG to PAT
Method A: Using the DXF Intermediate Step (Online Converters)
This is often the quickest method if you do not want to install additional plugins. Select your prepared geometry in AutoCAD.
Use the DXFOUT command and save the file as a DXF (AutoCAD 2000 version) to ensure maximum compatibility.
Upload your DXF to an online converter (such as DotSoft or other CAD utility sites). Download the generated .PAT file.
In AutoCAD, use the HATCH command and navigate to the Custom tab to load your new pattern. Method B: Using AutoCAD Express Tools (SuperHatch)
If you don't necessarily need a standalone .PAT file but want to use a DWG block as a hatch, use the SUPERHATCH command. Type SUPERHATCH in the command line. Select Block. Choose the block you want to use from your current drawing.
Follow the prompts to set the scale and placement. AutoCAD will treat the DWG block as a repeating pattern directly within the drawing. Method C: Using Third-Party Plugins
For professional users who create custom patterns frequently, specialized plugins provide a more seamless experience:
HatchKit: A dedicated tool widely recommended by Autodesk Support for visually designing and exporting PAT files from DWG data. convert dwg to pat file
PatGen: A lightweight utility specifically built to grab geometry from AutoCAD and write the PAT code automatically. How to Load and Use Your New .PAT File
Once you have generated your .PAT file, you need to make it accessible to AutoCAD:
Move the File: Place your .PAT file in the AutoCAD Support folder (typically found under Options > Files > Support File Search Path). Apply the Hatch: Open the HATCH command. Set the Pattern Type to "Custom." Select your file from the list. Common Troubleshooting
Hatch Too Dense: If you receive a "Hatch density is too high" error, increase the scale of your hatch or simplify the original DWG geometry.
Gaps in Pattern: Ensure your lines are perfectly snapped to their endpoints in the DWG before conversion to avoid visual gaps in the repeating tile. Block to PAT — AutoCAD Pattern Conversion #AutoCAD #Tips
Converting a DWG (AutoCAD drawing) to a PAT (hatch pattern) file is a frequent challenge for designers who want to turn unique geometry into reusable hatch fills. While AutoCAD doesn’t have a single "Save As .PAT" button, there are several effective workflows to achieve this—ranging from using built-in Express Tools to dedicated LISP routines. 1. The "Superhatch" Method (No .PAT File Required)
If you simply want to use a drawing as a pattern within your current project without creating a separate .pat file, use the SUPERHATCH command. This is part of the AutoCAD Express Tools. Step 1: Draw the geometry you want for your pattern.
Step 2: Convert that geometry into a Block using the BLOCK command. Step 3: Type SUPERHATCH in the command line.
Step 4: Select Block in the dialog, choose your created block, and specify the scale and rotation.
Step 5: Click inside the boundary you want to fill. AutoCAD will tile the block to create a custom hatch. 2. Exporting Existing Hatches to .PAT (LISP Routines)
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.
PatOut / GetPat: These are popular free LISP utilities available on platforms like CAD Forum. How to use:
Download the .lsp file and load it into AutoCAD using the APPLOAD command.
Run the command (e.g., GETPAT) and select the hatch in your drawing.
The routine will generate a .pat file and save it to your specified directory. 3. Converting Geometry to .PAT (Third-Party Tools) *weaver_terrazzo, Terrazzo pattern from DWG file ; Generated
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
Converting a DWG file to a PAT file is not a standard "Save As" function in AutoCAD, as these formats serve different purposes: DWG stores entire vector drawings, while PAT files contain text-based mathematical definitions for repeating hatch patterns.
To bridge this gap, you must use specific tools or manual workflows to extract or define the geometric data into a pattern format. Key Methods for Conversion SAVING AUTOCAD DWG AS .PAT FILE - Forums, Autodesk
Converting a DWG (AutoCAD Drawing) to a PAT (AutoCAD Hatch Pattern) file is a process typically used to create custom hatch textures from geometry you've drawn. Because DWG files contain complex data (arcs, layers, blocks) and PAT files are simple text-based descriptions of repeating lines, direct conversion requires specific preparation. Direct Conversion Method
The most reliable way to convert a specific drawing segment into a hatch pattern involves using AutoCAD and a secondary export step.
Prepare Geometry: Ensure your design consists only of Lines or Polylines. Standard PAT files do not support arcs or splines; these must be flattened or approximated with small straight segments.
Explode Blocks: If your geometry is part of a block, use the EXPLODE command to ensure the geometry is simple and clean.
Move to Origin: Move the pattern so its starting point is near the coordinates 0,0. This prevents alignment and math errors when the pattern repeats.
Export to DXF: Select the geometry and use the DXFOUT command. Save the file as a DXF (AutoCAD 2000 version) for maximum compatibility with converters.
Use a PAT Converter: Upload your DXF file to an online converter or use a dedicated tool like the Hatchkit Hatch Pattern Editor or an AutoCAD add-on like GetPat. Alternative: AutoCAD Express Tools
If you have the full version of AutoCAD, you can often use the SUPERHATCH command found in the Express Tools tab. While this doesn't create a standalone .pat file initially, it allows you to use a DWG block directly as a hatch pattern within your current drawing. Third-Party Software & Tools
Hatchkit: A professional-grade standalone editor that can import DXF/DWG and export a formatted .pat file.
AutoPAT: A popular LISP routine by Lee Mac that automates the creation of PAT files from selected AutoCAD objects.
ABViewer: While it supports many CAD conversions, it is primarily used for viewing and batch converting DWG to more common formats like PDF or PLT. Summary of Limitations Supported in PAT? Action Required Lines / Polylines Arcs / Circles Explode or convert to segmented polylines Splines Must be converted to straight line segments Layers / Colors PAT files are geometric definitions only Block to PAT — AutoCAD Pattern Conversion #AutoCAD #Tips
Converting a standard DWG (AutoCAD drawing) into a PAT (hatch pattern definition) file is a common yet nuanced task for CAD designers. While AutoCAD does not have a native "Save As .PAT" button, you can achieve this through specialized plugins, LISP routines, or manual workarounds that bridge the gap between drawing geometry and hatch definitions. Core Methods for Conversion Converting a standard DWG drawing into a custom
There are three primary ways to handle this conversion, depending on whether you want to extract an existing hatch or create a brand new pattern from geometry you’ve drawn. 1. Extracting Patterns with LISP Routines
If your DWG already contains a hatch pattern that you want to save as an external .pat file for use in other projects, the most efficient method is using a LISP utility.
PatOut / GetPat: These are popular freeware utilities. For example, by loading GetPat into AutoCAD via APPLOAD, you can simply select a hatch in your drawing and the tool will automatically generate a corresponding .pat file on your desktop.
Why use this? It’s the fastest way to "recover" a custom pattern if the original source file was lost. 2. Creating New Patterns from Blocks (SuperHatch)
For designers who have drawn a custom logo or geometric tile in a DWG and want it to behave like a repeating hatch, the Express Tools in AutoCAD offer a powerful alternative. Process: First, convert your custom drawing into a Block.
Command: Type SUPERHATCH in the command line. Select the "Block" option, choose your newly created block, and specify the boundary to fill.
Limitation: While SUPERHATCH creates a repeating pattern, it does not technically create a standalone .pat file that you can share or edit in Notepad; it lives within the specific drawing. 3. Converting Geometry to PAT Definitions (HGEN)
To create a true, portable .pat file from raw line geometry, specialized software or plugins like HGEN (Hatch Pattern Generator) are required. SAVING AUTOCAD DWG AS .PAT FILE - Forums, Autodesk
Published by [Your Name] – CAD Specialist
If you have ever stared at a complex geometric design in AutoCAD and wished you could reuse that exact shape as a fill pattern, you have likely searched for the elusive process to convert DWG to PAT file.
The short answer is: You cannot directly “convert” a DWG file into a single PAT file. Unlike converting a JPG to a PNG, a DWG (a full drawing database) and a PAT (a text-based pattern definition) are fundamentally different. However, you can extract a design from your DWG and define it as a custom hatch pattern.
In this 2,500-word guide, I will break down:
A DWG (DraWinG) is a proprietary binary file format used by AutoCAD. It stores:
A single DWG can contain a city layout, a mechanical part, or a complex logo. It stores patterns as objects, not as definitions.
| 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. |
Turn any DWG geometry into a seamless, intelligent AutoCAD hatch pattern without manual coding or grid-snapping.