Setting up before you start modelling

The main window divides into three areas, and the division reflects a real separation of concerns rather than a layout preference.

The rollback bar

A line at the bottom of the tree can be dragged upward to roll the model back through its own construction history, temporarily hiding the features below the line. This is the primary tool for reverse-engineering an unfamiliar model, investigating why a feature behaves as it does, and debugging a failed rebuild by isolating the step at which the failure begins.

Two related rules govern deletion, and both surprise newcomers. Deleting a feature does not delete its sketch — the sketch remains and can be reused. Conversely, a sketch cannot be deleted while a feature still consumes it; the feature must go first.

The system presents different command sets depending on what you are doing. Three modes are basic — part, assembly and drawing — and correspond to the three document types introduced in Part 01. Additional modes appear as capabilities are added: simulation, animation, analysis and machining among them.

The practical consequence is that a command you cannot find is frequently a command that belongs to a mode you are not in. Annotation tools appear in drawing mode; mates appear in assembly mode; sketch relations appear only while a sketch is open. Recognising this converts a large class of frustration into a one-second diagnosis.

Templates — also called start parts or master parts — are the mechanism that makes document-level configuration durable. A template is created like any other file and saved in the template format, after which it becomes available whenever a new document is started.

What a template can carry is broader than most people use:

Separate templates are normally maintained for parts, assemblies and drawings. Where a team shares work, templates belong on a network location rather than on individual machines — a template that exists on one designer's computer is a personal preference, not a standard.

Interaction conventions worth knowing early

• Left button selects; right button opens a context menu whose contents depend entirely on what is under the pointer. Most of the system's functionality is reachable this way.
• Rotating the mouse wheel zooms; pressing and holding it while dragging rotates the model.
• Multiple selection is by holding the modifier key and clicking, or by dragging a selection window — where only entities fully enclosed by the window are selected.
• The escape key exits sketching or any current operation, and is faster than finding the cancel control.
• Snapping to endpoints and midpoints can be lost; it is a system option and can be switched back on.

A model can be viewed from any angle during construction — the standard views being front, top, right and isometric, with back, bottom and left also available. But viewing and creating are two separate activities. Viewing is controlled by the orientation you select; construction is controlled by the active sketch plane.

Although the model may be viewed from any angle while building it, the practical convention is to view perpendicular to the active sketch plane. That alignment puts the sketch plane parallel to the screen, which is the only orientation in which sketch entities can be judged accurately as they are created.

Two practical constraints govern installation. The software is a native Windows application: running it on other operating systems requires either a dual-boot arrangement or virtualisation software, and virtualisation carries a performance penalty that matters for large assemblies. And the machine specification — memory, storage and a supported graphics adapter — should be checked against the vendor's published system requirements before purchase rather than after.

Beyond the built-in help, the wider resource set includes the vendor's own documentation and forums, community user groups and blogs, third-party training providers, and shared model libraries carrying parts, assemblies and macros contributed by manufacturers and users. Free viewer and markup applications also exist, which matter more than they first appear — they let a design be sent to someone without a licence, reviewed, marked up and returned. That capability is the subject of Part 16.