Can I change the linetype (e.g. to dashed) for just one segment in AutoCAD?

Short Answer

Yes — in AutoCAD, you can make just one segment appear dashed by first splitting the object at the desired points, then assigning a different linetype to that new piece with BREAK. This is the most common professional method for lines, polylines, and arcs. Limitation: it creates separate objects.

What You Need to Know Before

Warning: If the object is a polyline, breaking one segment creates separate geometry and may interrupt grips, widths, joined paths, or downstream editing. A locked layer or ByLayer linetype workflow can also prevent the dashed segment from displaying as expected.

How to Change One Segment to Dashed in AutoCAD

• Command: BREAK

• Shortcut: BR

• Quick Steps:

  1. On the Home tab > Modify panel, click Break, then select the line, polyline, or arc.
  2. Specify the first break point and second break point around the segment you want isolated.
  3. Select the new segment, then in the Properties palette set Linetype to Dashed (or move it to a layer with a dashed linetype). If needed, turn Linetype generation on for polylines.

Variables & Settings

• System Variable: PLINEGEN (Default: 0)

• Expert Setting: For polylines, PLINEGEN controls whether the linetype pattern runs continuously through vertices or restarts at each segment. If dashed display looks wrong after breaking a polyline, set PLINEGEN to 1 and regenerate the drawing.

Why it Fails

• Cause 1 (Geometry): The selected object is too short for the dashed pattern to display clearly, so it appears continuous.
• Cause 2 (layers/Locks): The object is on a locked layer, or its linetype is set ByLayer and the layer is still Continuous.
• Cause 3 (Command/Logic): You cannot assign a different linetype to only part of a single unbroken object; the segment must be separated first.

Quick Fix & Best Practice

• Quick Fix: Use BREAK to isolate the segment, then set Linetype in Properties and adjust LTSCALE if the dash pattern is not visible.
• Manager’s Verdict: Use this method when the graphic intent matters in plotted output. Avoid over-fragmenting production geometry unless the dashed segment is necessary for standards, coordination, or documentation clarity.

FAQ

Can I change one polyline segment to dashed without breaking it?

No, not as a unique segment property on one continuous polyline.

Why is my dashed segment still showing as continuous?

The linetype scale may be too large or too small, or the segment may be too short.

Is changing the layer better than changing object linetype?

Yes, in most office standards, putting the segment on the correct layer is cleaner and easier to manage.

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