How to compare CNC machining quotes from China
A CNC machining quotation is only comparable with another when both describe the same part and deliverable. Before choosing a supplier, match the drawing revision, material, quantity, tolerances, finish, inspection, packaging and shipping assumptions. This guide provides a practical review sequence rather than a supplier ranking or guaranteed price claim.
Build a like-for-like comparison
| Item | What to confirm |
|---|---|
| Drawing | Part number, revision, 2D drawing and matching 3D model |
| Material | Exact grade, stock assumption and approved alternatives |
| Quantidade | Quoted quantity, repeat quantity and one-time setup charges |
| Usinagem | Features, operations and any assumptions about tolerances |
| Acabamento | Deburring, coating, finish standard, color and masked areas |
| Inspeção | Critical dimensions, measurement method and requested report |
| Entrega | Packaging, destination, freight method and estimated schedule basis |
Questions to ask about each quotation
- Does the quote use the latest drawing revision and the exact material grade?
- Which dimensions or features have been treated as critical?
- Are finishing and inspection included, or priced separately?
- Are programming, setup, tooling or sample charges one-time or recurring?
- What is excluded from the quoted total, including packaging or freight?
- What assumptions could change the price or delivery estimate?
Watch for quote gaps
A low unit price can omit a required operation or assume a broader tolerance than the drawing. A higher number may include finishing, inspection or delivery that another offer lists separately. Compare the full scope and ask for revisions when assumptions are unclear.
For background on the main price inputs, see Fatores de custo de usinagem CNC. If you are preparing an inquiry, the página de cotação de usinagem CNC personalizada explains what information to send.
Record the selection basis
Keep the selected quote together with the approved drawing revision, material, quantity, finishing and inspection requirements. Document any exclusions, substitutions or schedule assumptions that the buyer accepted. This makes later order changes easier to compare with the original scope.
Quotes depend on the specific part and the information supplied. Ask for clarification before treating an estimate as a final commitment.