Why do the edges look strange in the "Rear" view?

Error description

You are modelling a moulding and are in the 3D view in the main window. If you display the edges here, the lines may form loops.

Figure 1: 3D, edges, view: rear

Cause of error

The lines shown are a projection of a 3-dimensional line onto a 2-dimensional surface. The line does not intersect; the spatial course and the projection give the impression that the line intersects.

Troubleshooting

Always take a look at the other views as well. In the view of the bar from behind, you are only interested in the 6 points shown. You can edit these in this view.

Figure 2: 3D, edges, view: rear, working points marked

If you switch to view I (inside), you can see how the lines run along the moulding.

Figure 3: 3D, edges, view: inside