In the Part-Editor, use the commands in the:
•Geometry menu and toolbar : to add sketch-elements. The toolbar is to the left of the graphic-area.
•Constraints menu and toolbar : to add Constraints to
oa sketch-element, and also
oits start-Point, its end-Point, and a center-Point.
To add a Constraint if very easy.
To DELETE a Constraint, you must first show the Constraint in the Selection-Window.
1.SHIFT+CLICK a sketch-element,
1.SHIFT-Click the start-Point, its end-Point, or center-Point of a sketch-element if the constraint was applied to a Point.
The sketch-element and its Constraints show in the Selection-Window.
2.Right-click the Constraint in the Selection-Window
In the contextual-menu:
In the Part-Editor, the Constraints toolbar is to the RIGHT of the graphic-area.
MERGE-POINTS : Deletes a Point. You cannot remove a 'Merged Point'.
•Use Merge-Points to join sketch-elements end-to-end, and to remove one of the Points.
•Use Merge-Points to make a sketch-path.
COINCIDENT Points : Does not delete a Point. You can delete a Coincident-Constraint later and move the Points apart again.
•Use a Coincident-Constraint to move together two Points, or a Point to a Line, or a Point to an Arc or Circle.
•Use Coincident-Constraints for construction geometry.
You cannot over-constrain a sketch-element in the Part-Editor (SolidWorks allows you to over-constrain, but you are given a warning).
A Point has 2 degrees-of-freedom (DOF). It you add a 'coincident constraint' between a Point and a Line, you remove 1 DOF, and 1 DOF remains. The Point can slide along the Line.
You cannot then add a new constraint between the same Point and a Point at one end of the Line. A constraint between a Point and a Point would remove 2 DOF, but only 1 DOF that remains.
1.SHIFT+CLICK a sketch-element in the graphic-area
The sketch-element and constraints added to it, show in the Selection-Window.
2.Right-click the constraint in the Selection-Window
3.Click Delete in the contextual-menu