Family Creation and Content
Family Creation and Content
Family creation tests your ability to build parametric families using reference planes, parameters, and constraints. You must understand family types (system, loadable, in-place), parameters (type vs. instance, shared), and form creation (extrusion, blend, sweep). Key concepts include constraint-driven geometry, family templates, and nesting. Traps often involve parameter types (e.g., using a type parameter when an instance is needed), reference plane locking, and form creation in the wrong context. Another common trap is shared parameters not appearing in schedules.
A frequent question asks how to make a family's dimension adjustable per instance. You create an instance parameter and associate it with a dimension. Also, nested families can be used to create complex assemblies.
Rule of thumb: Always flex your family by changing parameter values to ensure it behaves correctly. Use reference planes as the skeleton and lock dimensions to them.
Worked example: To create a parametric door family, start with a Door template, add reference planes for width and height, create type parameters for Width and Height, and dimension to the reference planes. Then create the door panel extrusion and lock it to the reference planes. Test by changing the parameter values.
Key points
- Use reference planes and constraints to drive geometry.
- Type parameters affect all instances; instance parameters vary per element.
- Shared parameters are needed for schedules and tags.
- Nested families allow complex content; manage their parameters.
- Always flex the family to verify behavior.