SolidWorks is a three-dimensional computer-aided design (CAD) program. CAD programs focus on making design easier and faster. You use SolidWorks to model an object by defining dimensions and relationships each part has. A coincident relationship, which tells SolidWorks that two points should always be touching, is a common and useful relationship in design. Coincident relationships can be used in both 2D sketch mode and 3D assembly mode to define your model.
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In 2D Sketch Mode
Step
Select a line, point, center line or temporary axis with the left mouse button.
Step
Hold the "Control" key and select the second line, point or temporary axis by left-clicking it. A properties box will appear on the left-hand side.
Step
Click the "Coincident" button in the Add Relations section of the properties box.
In 3D Assembly Mode
Step
Click the "Mate" assembly tool.
Step
Click the first point, edge or face that should be coincident.
Step
Click the second point, edge or face. The Standard Mates bar will pop up.
Step
Select "Coincident" in the Standard Mates bar.