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When you open PurusMech, you'll see the home screen. Click New to start a blank project. Your workspace opens with a default 3D view ready for modeling.
All solid features begin with a sketch. In the Sketch tab, click New Sketch to start. If you have a planar face selected, the sketch will be placed on it automatically; otherwise, you'll select a plane or face to sketch on.
Once you've drawn a closed sketch profile (using Line, Rectangle, Circle, or other draw tools), finish the sketch. Then in the Solid tab, click Extrude. Set the extrusion distance (millimetres by default; change the unit in Settings) and click to create your first 3D solid feature.
Click the Save button on the toolbar or press Ctrl+S to save your work as a .pmweb file. This format preserves your complete parametric model for future editing.
Click the Open button on the toolbar (or Open on the home screen) to load a previously saved .pmweb file.
Install PurusMech to open .pmweb files by double-clicking them. Choose Install app in the account menu (it appears when your browser can install the app), then double-click a .pmweb part or .pasm assembly in File Explorer.
The Sketch tab contains all tools for creating and editing 2D profiles. Key drawing tools include:
Click Smart Dimension in the Dimensions group to add dimensions that control your sketch geometry. You can create horizontal, vertical, radial, angular, and ordinate dimensions. Click the dimension and edit the value to drive the geometry parametrically.
Use Add Relation in the Relations group to apply geometric constraints. Available relations include:
A sketch is fully defined when all geometry is constrained by dimensions and relations, with no degrees of freedom. Fully defined geometry appears in black; underconstrained geometry appears in blue. A fully defined sketch is essential for features like Extrude or Revolve.
When your sketch is complete, click the checkmark in the corner, or press Enter or Escape, to finish the sketch. Your sketch is now ready to be used as a profile for solid features.
These features create 3D solids from 2D sketch profiles:
Push a sketch profile perpendicular to create a 3D block. Specify distance, direction, and operation (Join, New Body, or Cut).
Rotate a sketch profile around an axis to create rotational features like cylinders, cones, and shafts.
Move a sketch profile along a path to create complex shapes like tubes or helical features.
Blend between multiple sketch profiles to create flowing transition surfaces and shapes.
These features add material or structure to your existing solid:
Click Hole in the Modify group to add holes with options for:
Round edges (Fillet) or cut corners (Chamfer). Specify radius or distance and select edges to modify.
Convert a solid to a thin-walled shell by removing faces and applying uniform wall thickness.
Duplicate features in linear or circular arrays (Linear, Circular, Sketch-Driven).
Delete faces, move/rotate faces, or replace faces with planes for advanced modeling.
Manage multiple solid bodies in one design:
The Assembly tab lets you insert multiple parts and position them using mates. Use Insert Part to add saved .pmweb files to your assembly, then apply spatial relationships using Position, Coincident, Distance, Angle, and other mate types. The Solve Mates command resolves all constraints.
Available mate types include standard mates (Coincident, Distance, Angle, Parallel, Perpendicular), mechanical mates (Cam-Follower, Belt, Screw, Universal Joint), and component patterns for duplicating parts.
The Drawing tab provides tools for creating 2D engineering drawings, geometric dimensioning and tolerancing (GD&T), and annotations. Create sheets, add views, apply dimensions and GD&T symbols, and generate Bills of Materials.
Load external CAD geometry in STEP format from the Interop tab. The imported solid becomes a new body in your current project.
| Format | Use |
|---|---|
| STEP (.step) | Industry standard CAD interchange; preserves geometry precisely |
| STL (binary/ASCII) | 3D printing and mesh visualization |
| OBJ | 3D visualization and graphics pipelines |
All export functions are in the Interop tab.
Press Shift + 1 through 7 to snap to standard views:
Click geometry in the 3D view to select edges, faces, or entire features. In sketches, click points, lines, and curves. Drag with Shift held to box-select.
When drawing in sketches, the system automatically detects nearby points, lines, and centers (object snap). Hold Ctrl while drawing to suppress inference and place geometry freely.
PurusMech is in active development. During this beta period: