Adding geometry in SolidWorks is fundamental to creating any 3D model, involving a systematic process that builds from 2D sketches to complex 3D features and auxiliary reference elements. This guide will walk you through the primary methods, from basic sketching to advanced feature creation and the use of reference geometry.
The Foundation: Sketching in 2D
Most 3D geometry in SolidWorks begins with a 2D sketch. A sketch defines the profile or path that will be used to create a 3D feature.
How to Start a Sketch
- Select a Plane or Face: Choose a flat plane (like Front, Top, or Right Plane) or an existing flat face on your model where you want to draw.
- Activate Sketch Mode: Click the Sketch tab on the Command Manager and select the Sketch tool (often represented by a pencil icon). Alternatively, right-click on your chosen plane/face and select "Sketch."
Basic Sketch Entities
Once in sketch mode, you can draw various 2D shapes:
- Lines: Straight segments connecting two points.
- Circles: Defined by a center point and a radius or diameter.
- Rectangles: Drawn by two opposite corners, or by a center and corner.
- Arcs: Portions of a circle, defined by three points or a center and two endpoints.
- Splines: Smooth, curved lines defined by a series of points, ideal for organic shapes.
- Polygons: Regular multi-sided shapes.
Defining Your Sketch: Relations and Dimensions
For a robust and predictable model, your sketches must be "fully defined." This is achieved through:
- Geometric Relations: These are constraints that define how sketch entities relate to each other.
- Examples: Horizontal, Vertical, Coincident, Tangent, Parallel, Perpendicular, Equal, Midpoint.
- To add a relation, select two or more sketch entities and choose the desired relation from the context toolbar or the PropertyManager.
- Dimensions: Numerical values that define the size and position of sketch entities.
- Use the Smart Dimension tool to add lengths, angles, radii, and diameters.
- A fully defined sketch will have all its lines and points appear black (instead of blue).
Building 3D Forms: Features
Features transform 2D sketches into 3D solid or surface geometry. They are the building blocks of your 3D model.
Common Feature Types
| Feature Type | Description | Sketch Requirement | Example Use |
|---|---|---|---|
| Extrude Boss/Base | Pushes a 2D profile along a straight path to add material. | Closed profile | Creating a basic block or cylinder. |
| Revolved Boss/Base | Rotates a 2D profile around an axis to add material. | Closed profile and an axis | Creating symmetrical parts like shafts, bottles, or domes. |
| Sweep Boss/Base | Pushes a 2D profile along a path to add material. | Two sketches: profile and path | Creating curved pipes, handles, or complex wire shapes. |
| Lofted Boss/Base | Blends multiple 2D profiles together to create a smooth, complex shape. | Two or more closed profiles | Designing ergonomic shapes, boat hulls, or airfoils. |
| Extruded Cut | Removes material by pushing a 2D profile along a straight path. | Closed profile | Drilling holes, creating slots or pockets. |
| Revolved Cut | Removes material by rotating a 2D profile around an axis. | Closed profile and an axis | Machining grooves, internal bores, or turning operations. |
| Fillet/Chamfer | Rounds or bevels edges. | No sketch needed, directly applied to edges | Softening sharp edges for safety or aesthetics. |
| Shell | Hollowing out a part, leaving a wall thickness. | No sketch needed, applied to solid body | Creating enclosures, housings, or plastic parts. |
Applying Features
- Create a Sketch: Ensure you have a closed, fully defined sketch (for most features like extrude, revolve, sweep, loft).
- Select the Feature Tool: Go to the Features tab on the Command Manager.
- Define Parameters: In the PropertyManager, specify dimensions (e.g., extrusion depth, angle of revolution), directions, and other options.
- Confirm: Click the green checkmark to create the feature.
Auxiliary Elements: Reference Geometry
Reference geometry provides the framework for creating more complex features and assemblies. These elements (planes, axes, points, coordinate systems) don't represent the final part but are crucial for positioning sketches and features.
Creating Reference Planes
New planes are essential when you need to sketch or apply features on a surface that doesn't currently exist or isn't parallel to the standard planes. This is particularly useful for creating features at an angle, in the middle of a part, or offset from an existing face.
To add a new reference plane:
- Access the Plane Wizard:
- Navigate to Features > Reference Geometry > Plane on the Command Manager.
- Alternatively, go to Insert > Reference Geometry > Plane from the drop-down menu.
- Define the Plane: In the Plane PropertyManager, you can select up to three references to define the new plane. These references are listed as First Reference, Second Reference, and Third Reference.
- Common Reference Combinations:
- One Reference (e.g., existing plane/face + offset distance): Select a flat surface and specify an offset distance.
- Two References (e.g., two parallel faces, an edge and a point, two non-parallel edges): For instance, selecting two parallel faces will create a mid-plane, or selecting an edge and a point will create a plane through them.
- Three References (e.g., three non-collinear points): Defines a unique plane passing through all three points.
- Common Reference Combinations:
- Adjust Options: Review and adjust options like "Flip offset" or angle if necessary.
- Confirm: Click the green checkmark to create the new plane.
Other Reference Geometry
- Reference Axes: Used as axes of revolution, for circular patterns, or to define cylindrical features. Created from two planes, two points, a cylindrical face, or a point and a face.
- Reference Points: Can be used as sketch origins, for patterns, or as a reference for other geometry. Created at the intersection of lines, faces, or at specific coordinates.
- Coordinate Systems: Defines a new origin and orientation for specific operations, useful in complex assemblies or for importing/exporting data.
By mastering these methods – sketching, creating features, and leveraging reference geometry – you can effectively build and modify any geometry within SolidWorks, bringing your designs to life.
