When you use the Join command to join objects, the following rules apply.

Lines:
• Segments must be collinear.
• Segments can overlap.
• Segments can have a gap between them.

Polylines and splines:
• Must be coplanar.
• Must share a common endpoint.
• Segments cannot overlap.
• Lines and arcs can be joined to polylines if a polyline is selected as the source object.

Arcs:
• Must share the same circular path.
• Segments can overlap.
• Segments can have a gap between them.

Elliptical Arcs:
• Must share the same elliptical path.

Joining Arcs or Elliptical Arcs
When you join arcs or elliptical arcs together, the source object is always extended to the other objects in a counterclockwise direction. In the following image, the source arc is selected at point (1) while the other arc is selected at point (2). The source arc is extended counterclockwise to meet the other arc.

Procedure: Joining Lines with the Join Command

The following steps give an overview of joining lines using Join.
Procedure: Converting an Arc to a Circle with the Join Command
The following steps give an overview of converting an arc to a circle using Join.
1. On the Modify toolbar, click Join.
2. Select the source line.

3. Select the other lines to join to the source line and press ENTER.

 
The selected line segments are joined together.

Procedure: Converting an Arc to a Circle with the Join Command
1. On the Modify toolbar, click Join.
2. Select an arc.

3. Right-click and select Close on the shortcut menu.
4. The arc is converted to a circle.

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