AutoCAD

How to Use Extend in AutoCAD 2018?

Introduction to the Extend Functionality in AutoCAD

The Extend command within AutoCAD is a powerful feature that allows users to stretch lines or shapes until they touch the edges of existing objects. This function is incredibly useful for precise architectural and engineering designs, where maintaining accurate dimensions is essential. Here’s a step-by-step guide on how to effectively use the Extend feature in AutoCAD 2025.

Step-by-Step Guide to Using the Extend Command

Step 1: Initiate the Command

Begin by navigating to the Home tab on the ribbon at the top of the screen. Locate the Modify panel and click on the “Extend” command. You can also invoke the command by typing “EXTEND” in the command line and pressing Enter.

Step 2: Select Boundary Objects

After initiating the Extend command, you will be prompted to select the boundary edges. These edges define where your selected objects will extend to. Use your mouse to click on the objects that will serve as boundaries, such as lines, arcs, or polylines. Press Enter once you have finished selecting all relevant edges.

Step 3: Choosing Objects to Extend

Next, select the objects you want to extend. Click on the lines or shapes that need to reach the selected boundary edges. After selecting all necessary objects, press Enter again to finalize your selection.

Step 4: Utilizing Additional Options

During the extending process, several additional options are available:

  • Shift + Click: By holding the Shift key while selecting objects, you can trim them instead of extending.
  • Fence and Crossing: These selection methods allow for more complex designs, letting you select multiple objects simultaneously.

Step 5: Confirming Extensions

Once the objects are selected, AutoCAD will extend them to the defined boundaries. If you want to undo an extension, simply type “U” for undo command if necessary.

Understanding the Extend Function

The Extend command works by analyzing the selected boundary edges. AutoCAD treats these boundaries as guides, allowing the software to automatically stretch the selected objects until they converge with these edges. It is crucial for users to comprehend how the boundaries dictate the extension process, ensuring that objects align perfectly with the design intent.

Using Edgemode for Precision

When utilizing the Extend command, users can engage Edgemode, which allows for an enhanced extending or trimming experience. This mode ensures that selected objects extend seamlessly to imagined extensions of edges, ensuring precision in design.

Differences Between Extend and Trim

While Extend stretches objects to meet boundaries, Trim does the opposite. The Trim command removes parts of objects up to an intersection point. It’s vital to understand when to use each command for efficient drawing processes.

Frequently Asked Questions

1. Can I extend multiple objects at once in AutoCAD?
Yes, you can extend multiple objects simultaneously by selecting them while using the Extend command. Ensure that all desired objects are selected before pressing Enter.

2. Is there an alternative method to extend lines other than the Extend command?
Yes, lines can also be extended manually by selecting the line and dragging its endpoint towards the desired object, although this method lacks the precision of the Extend command.

3. What should I do if the Extend command isn’t working as expected?
If the Extend command does not function properly, check if your object selection is correct. Ensure that the boundaries are valid objects and that you are not in any restricted mode that prevents modifications. Restarting AutoCAD may also resolve temporary glitches.

About the author

Wei Zhang

Wei Zhang

Wei Zhang is a renowned figure in the CAD (Computer-Aided Design) industry in Canada, with over 30 years of experience spanning his native China and Canada. As the founder of a CAD training center, Wei has been instrumental in shaping the skills of hundreds of technicians and engineers in technical drawing and CAD software applications. He is a certified developer with Autodesk, demonstrating his deep expertise and commitment to staying at the forefront of CAD technology. Wei’s passion for education and technology has not only made him a respected educator but also a key player in advancing CAD methodologies in various engineering sectors. His contributions have significantly impacted the way CAD is taught and applied in the professional world, bridging the gap between traditional drafting techniques and modern digital solutions.