About Locked and Unlocked Dimensions
You can lock dimensions in Sketcher. Locking of dimensions allows you to avoid modifications made to the sections outside the Sketcher mode by accidentally dragging a vertex or an entity. The locked state of the dimension is maintained when you quit or re-enter Sketcher mode.
You can also set Sketcher to lock all user-defined dimensions automatically by setting the value of the
sketcher_dimension_autolock configuration option to
yes. Alternatively, click
File >
Options >
Sketcher >
Lock user defined dimensions.
After you set this option, all dimensions that you subsequently create or modify are locked. Dimensions created before you set automatic locking maintain their status.
|  The locked state of a dimension is not retained if the dimension is referenced in a relation, as the relation takes priority over the locked status of the dimension. |
To unlock a selected dimension, right-click and choose Unlock on the mini toolbar.
You can set the color for locked dimensions by clicking
File >
Options >
System Appearance >
Sketcher. Select a color in the
Locked dimension area.