Can you edit/extend the length of an existing arc about its original center point?

I’d like to change the length of an existing arc by extending its length about its center. As per the documentation, which says you can use the move tool to drag the end of an arc to change its length. Note that when you start in the SU for Web documentation, it then sends you to the SU documentation…not sure if there are limitations on this functionality in the Web version. In SU for Web, it merely moves the entire arc. Is this the expected behavior in SU for Web, or is there more specific documentation for SU for Web which defines its limitations. Or am I doing something wrong?

See the pics “Original Arc” and “Desired Result” for an example of what I’m trying to do.

Here’s what I’ve tried:

  1. Select the arc to modify…See pic “Arc Definition.”
  2. Select the Move tool.
  3. Select an endpoint on the arc and hold down the left-mouse button and try to drag…it moves the entire arc…See pic “Attempt to Move Endpoint by Dragging.”

TIA for any insights.




I gather you want an arc of the same radius but continued to be longer. SketchUp can’t do that. Redraw the arc. You can move the endpoint by NOT selecting the geometry first, but that creates a different arc radius.