Why Reference Selection Matters
Prioritizing primary datum planes over cosmetic fillets to avoid upstream sketch edits breaking child assembly definitions.
Reference Discipline
Geometric Reference Selection
The stability of an entire assembly depends on which faces, planes, and edges a mate references. These guides show how to anchor constraints to geometry that survives revision.
Anchoring to Stable Entities
Mating to origin planes and primary datums instead of cosmetic fillets or draft faces is the single most effective defense against dangling mates.
What Changes When a Reference Face Moves?
Tracing assembly rebuild propagation across multi-tier subassemblies when source part faces undergo dimension updates.
Coincident Versus Concentric Relationships
A practical geometric study illustrating when axial cylinder concentricity should precede planar face contact mating.
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