Mirror in a sketch

Key M. Select the entities, then the axis: the selected line serves as one, and if there is none the Y axis is used.

Half of an outline and its reflection about a construction axis.
Half of an outline and its reflection about a construction axis.

The dashed line between the circles is construction geometry: it holds the intent but never becomes material.
The dashed line between the circles is construction geometry: it holds the intent but never becomes material.

Symmetry by constraint, not by copy

Mirrored entities are tied to the original by symmetry. That means a change to one half carries over to the other by itself, and that only one half needs defining — the other gets its definition for free.

How it is used

For a symmetric part you draw one half, put the centre line in as construction geometry (key X) and mirror it. The centre line will not become part of the body profile but stays as the support of the symmetry.

Offset →