A-R03
Datum reference frames — Reference record
The drawing datum scheme and the physical fixture are related descriptions, not interchangeable objects. Datum precedence affects the intended setup.
| Reference record | Working notes |
|---|---|
| Overview | Datum reference frames |
| Practical example | Place the drawing reference beside each contact group and mark which face is loaded first. |
| Limits and interpretation | A convenient flat face is not automatically a specified datum feature. |
| Document control | Reference edition 2026.11 |
Measurements and examples are descriptive, not acceptance criteria.