How to Join Polylines in AutoCAD 2017?

Understanding Polylines in AutoCAD 2025

Polylines are a versatile tool within AutoCAD, allowing users to create connected lines and curves as a single object. With the capability to join multiple segments, polylines can enhance drawing efficiency and accuracy. Here’s a comprehensive guide on how to join polylines in AutoCAD 2025.

Initial Steps to Join Polylines

1. Access the Modify Panel:
   Begin by selecting the “Modify” tab within the AutoCAD interface. This panel houses various editing tools needed for your drawing tasks.

2. Select the Edit Polyline Option:
   Look for the "Edit Polyline" option. This will allow you to manipulate existing polylines or create new segments as needed.

3. Choose the Polyline to Edit:
   Click on the polyline segment you wish to modify. This action will activate the editing features for that specific object.

Joining Polylines

1. Activate the Joining Command:
   Once the desired polyline is selected, enter the command by typing j for “Join” in the command line. This command informs AutoCAD that you intend to connect multiple entities.

2. Select Additional Polylines:
   Now, proceed to select other polylines, lines, arcs, or splines that are in close proximity to the initial polyline you selected. Ensure they are positioned end-to-end for a successful join.

3. Finalize the Command:
   After selecting all intended segments, press the Enter key to complete the joining action. The selected items will now be combined into a single polyline.

Troubleshooting Joining Issues

• Check for Gaps:
  If the lines do not join, inspect the selected segments for minute gaps or misalignments. This could be due to tiny differences in length or elevation.

• Adjust the Fuzz Factor:
  Consider modifying the fuzz distance—a setting in AutoCAD that defines how closely endpoints need to be positioned to be joined. This can help in cases where points are nearly touching but not quite aligned.

Converting Lines to Polylines

In some cases, you may want to convert separate lines into a polyline before joining them.

1. Initiate the Polyline Edit Command:
   Type PE at the command line and press Enter. This starts the polyline edit process.

2. Select the Objects:
   Choose the individual lines you wish to convert. You can select multiple objects by typing “Multiple” in the command prompt when prompted.

3. Complete the Edit:
   Follow through with the commands as prompted to finalize the conversion of your selected lines into a singular polyline.

Frequently Asked Questions

1. Can I join polylines that are not directly connected?
Joining will require them to be end-to-end. If there are gaps, consider closing those gaps by moving or adjusting the lines.

2. What should I do if I encounter a problem during the joining process?
Ensure there are no gaps, and check the 3D elevations of segments. Use the Properties palette to verify Start Z and End Z values.

3. Is it possible to reverse the join after completing it?
Once polylines are joined, they cannot be separated through the join command. You would need to explode the resulting polyline to manage individual segments.