A CNC machining RFQ is only as reliable as the information behind it. When a supplier receives a 3D model without a controlled drawing, a material family without an exact grade, or a quantity without finishing and inspection requirements, the estimator has to ask questions or make assumptions. Either result can delay the quotation and make competing prices difficult to compare.
This CNC machining RFQ checklis explains what engineers and purchasing teams should send when requesting prices for custom machined parts. A complete package helps the supplier understand the geometry, delivered condition, quality requirements and commercial scope before calculating material, machining, finishing, inspection and logistics costs.
What is a CNC machining RFQ?
An RFQ, or request for quotation, is the package a buyer sends to a manufacturer to request pricing and delivery information for a defined scope of work. For a machined component, the CNC machining RFQ should establish what part is being quoted, which revision applies, what condition must be delivered, how many parts are required and what evidence will be used to accept them.
A useful CNC machining RFQ does more than ask, “How much will this part cost?” It gives each supplier the same technical and commercial basis for its quotation. This makes prices easier to compare and reduces the risk that one supplier includes finishing, inspection and packaging while another quotes machining only.
CNC machining RFQ checklist at a glance
| RFQ item | What to send | Why it matters |
|---|---|---|
| Part identity | Part number, part name, drawing revision, and units | Prevents the wrong component or revision from being quoted. |
| 3D geometry | Native CAD file or neutral solid model such as STEP | Supports geometry review, material estimation, and manufacturability analysis. |
| Technical drawing | Controlled 2D drawing in PDF or another approved format | Communicates tolerances, datums, threads, finishes, and inspection notes. |
| Material | Exact material grade, alloy, temper, condition, and applicable specification | Affects availability, machining strategy, dimensional stability, and price. |
| Quantity | Current order quantity, requested price tiers, and estimated annual usage when relevant | Changes setup-cost allocation, material purchasing, and the production approach. |
| Tolerances | Critical dimensions, GD&T, datum references, fits, and general tolerances | Defines the required machining accuracy and inspection effort. |
| Surface condition | Finish, coating, surface texture, color, masking, and cosmetic requirements | Determines secondary processing, dimensional allowances, and handling requirements. |
| Secondary operations | Heat treatment, grinding, inserts, marking, assembly, cleaning, or testing | Ensures that the quotation covers the complete delivered part. |
| Inspection | Inspection reports, sampling plan, certificates, and traceability requirements | Ensures that quality-control and documentation costs are included. |
| Delivery | Delivery destination, required date, packaging, and labeling requirements | Establishes the production schedule and logistics scope. |
| Commercial terms | Currency, quotation validity, confidentiality, and purchasing requirements | Reduces administrative uncertainty and improves quote comparison. |
Common mistakes that delay a CNC machining RFQ
Common mistakes |
Details |
|---|---|
Sending only a screenshot | A screenshot can illustrate a concept, but it does not provide reliable geometry, tolerances or scale. Send a usable model and drawing whenever available. |
Naming only a material family | “Aluminum” or “steel” forces the supplier to request clarification or price an assumed grade. Specify the grade and condition. |
Tightening every tolerance | Blanket tight tolerances add manufacturing and inspection effort. Apply tighter controls to features that need them. |
Omitting quantities | Setup and programming costs affect one prototype very differently from a repeat order. Give the actual quantity and any useful pricing tiers. |
Leaving finishing until later | Finishing may change dimensions, material sourcing, lead time, inspection and packaging. Include it in the initial RFQ. |
Requesting documents after production | Material certificates, first-article reports and traceability should be agreed before the order so the supplier can plan and price them correctly. |
Sending conflicting revisions | A model and drawing from different revisions can produce an invalid quotation. Check the complete package before sending it. |
How to compare CNC machining quotations
| Comparison point | Questions to ask |
|---|---|
| Technical scope | Did the supplier quote the correct files and drawing revision? |
| Material | Are the material grade, condition, certificates, and permitted substitutions clearly stated? |
| Quantity | Does the unit price apply to the requested production quantity? |
| Tolerances | Has the supplier accepted every critical tolerance, fit, thread, and GD&T requirement? |
| Surface finishing | Are all finishing and secondary processes included? |
| Inspection | Which inspection activities, dimensional reports, and certificates are included? |
| Tooling and setup | Are programming, fixtures, special tools, and setup charges included or listed separately? |
| Lead time | Does the lead time include material sourcing, machining, finishing, inspection, and delivery? |
| Packaging and freight | Which packaging, shipping, taxes, and logistics costs are included? |
| Assumptions and exclusions | Has the supplier documented every deviation, assumption, and excluded operation? |
| Quotation validity | How long will the quoted price and lead time remain valid? |
Copyable CNC machining RFQ checklist
Use this list before sending your package:
– [ ] Part number and revision are consistent across every file
– [ ] 3D CAD model opens correctly and uses the stated units
– [ ] Controlled 2D drawing is included
– [ ] Exact material grade and condition are specified
– [ ] Current quantity and requested price tiers are listed
– [ ] Critical tolerances, datums and GD&T are defined
– [ ] Thread and insert requirements are complete
– [ ] Surface finish, masking and cosmetic criteria are specified
– [ ] Heat treatment and other secondary operations are included
– [ ] Inspection reports, certificates and traceability needs are listed
– [ ] Packaging, labeling and delivery requirements are stated
– [ ] Confidentiality and file-transfer requirements are addressed
– [ ] Engineering and commercial contacts are identified
– [ ] Unresolved decisions are clearly marked
Conclusion
A strong CNC machining RFQ reduces guesswork. It tells the supplier what part to price, what condition to deliver, how the component will be accepted and which commercial terms apply. That improves quotation accuracy and gives purchasing teams a fairer basis for comparing suppliers.
Use this CNC machining RFQ checklist before sending your next project. When your model, drawing and requirements are ready, review MXY’s CNC machining services] and submit your files for review and quotation. Confirm process availability, achievable tolerances, material sourcing, finishing, inspection documentation and delivery expectations for the specific part before placing an order.
Frequently asked questions
What should be included in a CNC machining RFQ?
A complete RFQ normally includes a controlled 3D model, 2D drawing, exact material specification, quantity, critical tolerances, surface finish, inspection requirements, secondary operations, packaging and delivery information. Include any certificates or traceability records required with the shipment.
Should I send both a 3D model and a 2D drawing?
Send both when they are available. The model communicates complete geometry, while the drawing communicates tolerances, datums, threads, finishes, notes and acceptance requirements that may not be contained in the model.
What file format is best for a CNC quote?
STEP and Parasolid are commonly useful neutral solid-model formats, but supplier compatibility should be confirmed. A controlled PDF drawing should accompany the model when requirements such as tolerances, threads, surface finish and inspection must be communicated.
Can I request a quote without a finished drawing?
You can request a preliminary manufacturability or budget discussion with incomplete design data, but label it accordingly. A firm production quotation normally requires controlled requirements and clearly documented assumptions.
Why does quantity change the unit price?
Programming, setup, workholding and some inspection activities occur regardless of whether one part or many parts are produced. Higher quantities distribute these costs across more units and may justify different production methods or material purchasing.
How can I receive a more accurate CNC machining quote?
Send complete, consistent files and distinguish mandatory requirements from preferences. Define the delivered material condition, tolerances, finishing, inspection scope, quantity and delivery needs, then respond promptly to engineering questions.
