Define What âUltra Precisionâ Means for the Part
Ultra precision CNC machining is a broad phrase, not a measurable specification by itself. A buyer should define the actual functional dimensions, datum relationships, finish, material, and inspection evidence required for the part. Do not rely on a generic promise of sub-micron accuracy or a mirror finish unless the supplier has reviewed the drawing and confirmed the requirement for that project.
Start with the Functional Need
Explain whether the part must align, seal, move, mate with another component, or meet a stated surface condition. Identify the features that control that function and put dimensions and tolerances on the controlled drawing. Keep general dimensions separate from the few features that need tighter control.
- Identify the part number, material, and drawing revision.
- Mark functional datums and critical dimensions.
- State surface finish requirements and how they will be accepted.
- List measurement records and sample approvals required.
- Ask the supplier to confirm feasibility and inspection scope against the drawing.
For guidance on close dimensional relationships, see the guida alla lavorazione a tolleranza stretta. For defining critical CNC dimensions, review the high-precision requirements checklist.
Confirm the Measurement Basis
Ask which features will be measured, what records will be supplied, and whether results are required for a sample, first article, or production lot. If the requirement is unusual or affects several related parts, request a part-specific review before accepting a quote. Keep assumptions and exclusions in writing.
Domande frequenti
Is ultra precision a defined tolerance?
No. The phrase must be translated into dimensions, tolerances, finish requirements, and inspection criteria for the part.
Should I request sub-micron tolerances on every feature?
No. Identify only the features that control the design function and have the supplier review those requirements.
How do I specify a mirror finish?
Use a measurable surface finish requirement and state the inspection or acceptance method rather than relying on a visual phrase alone.
What records should I request?
List the critical dimensions, required measurement reports, material records if needed, and sample approval steps in the RFQ.
Can a supplier confirm an ultra-precision requirement before seeing the part?
Ask for drawing review of material, geometry, quantity, setup, finish, and measurement method before treating the requirement as confirmed.