RFQ preparation resource

How to Prepare RFQ Drawings for CNC Machining

A complete RFQ package helps your supplier quote faster, review manufacturability earlier, and avoid preventable clarification loops. Good geometry is only part of the job. A quote-ready package also needs material, quantity, tolerance, finish, inspection, and revision detail that keeps the supplier from guessing.

Use this guide to package 2D drawings, 3D files, material notes, quantity plans, tolerance callouts, surface finish requirements, and inspection requests before you submit a machining inquiry. It works best alongside design review, tolerance planning, and the final RFQ submission.

Quote-readiness card

  • 3D model: STEP, STP, IGES, X_T, or native CAD
  • 2D drawing: units, revision, dimensions, callouts
  • Material: exact alloy, grade, temper, or cert note
  • Quantity: prototype, pilot run, or repeat demand
  • Critical features: tolerances, threads, datums, finish zones
  • Inspection: FAI, dimensional report, CoC, or material certs
Best fit OEM buyers and engineers trying to send a cleaner CNC RFQ package
Primary CTA Submit complete RFQ
Related pages tolerance guide, quality control, secure drawing upload
engineer reviewing RFQ drawing package for CNC machined parts

A quote-ready RFQ package includes more than geometry

If you want an accurate machining quote, the supplier should not have to guess your material, quantity pattern, finish expectations, thread standard, or the few dimensions that actually control assembly. The RFQ package should make those items visible from the start.

The strongest submission normally combines a 3D model for geometry, a 2D drawing for controlled notes, and the commercial context that affects process choice. That usually means the material grade, expected quantity, target timing, destination, and any document requirements or inspection requests that should be priced into the review.

  • Useful when buyers want fewer clarification rounds before quoting
  • Useful when a part has finish, thread, sealing, or cosmetic requirements
  • Useful when the RFQ may move from prototype into repeat low-volume supply

RFQ drawing package matrix

Use this matrix to check whether the quote package is only technically possible, or truly ready for a faster and more accurate review.

Item Why it matters Minimum for quote Best practice
3D model Gives the supplier fast access to geometry, machining access, and overall shape STEP, STP, IGES, X_T, or native CAD Pair with a controlled 2D drawing for all critical notes
2D drawing Controls tolerances, threads, finish, revision, and inspection intent PDF with units and revision block Add section views, datum logic, and clear feature notes
Material callout Stops re-quoting caused by vague or changed stock assumptions Alloy or grade Include temper, hardness, or certification request
Quantity Affects setup spread, process route, and fixture assumptions Prototype lot size Show pilot-run and repeat demand if known
Critical tolerances Tells the supplier where precision matters and where it does not General tolerance note Mark fit-critical dimensions and datums individually
Finish and cosmetics Changes process sequence, masking, handling, and cost Finish name Add Ra, cosmetic zones, masking, or edge-break notes
Inspection request Sets the quality scope before the quote is released Basic final inspection State CMM, FAI, dimensional report, CoC, or material cert need
Delivery note Helps the supplier align timing, packaging, and export planning Target date Add destination country and NDA requirement if relevant

2D, 3D, or sample only?

A supplier can often review less-than-perfect inputs, but that does not mean the package is ready for a controlled quote comparison. This table shows how submission quality changes with design maturity.

What you have Can a supplier quote? What is usually missing Best next step
3D model + 2D drawing Yes Often only commercial details remain Submit the full RFQ
3D model only Usually for a budgetary review Tolerances, threads, finish, cosmetic zones, inspection scope Add the 2D drawing before final comparison
2D drawing only Sometimes Full geometry interpretation and CAM efficiency Add a 3D model if possible
Physical sample only Only roughly Controlled dimensions, revision status, and note clarity Build a controlled drawing package first
CNC machining RFQ package with drawing, CAD reference, and inspection notes

What should be called out directly on the drawing

A controlled 2D drawing should remove guesswork. At minimum, the drawing should show units, revision status, material, general tolerance logic, and the feature-level notes that matter to function or appearance.

Revision controlUse a visible revision block and one released file set.
Critical dimensionsMark fit-critical features instead of applying tight tolerance to the full part.
Threads and holesState standard, size, depth, and any verification requirement.
Finish calloutsIdentify coating, Ra, cosmetics, masking, and edge-break instructions.
Material noteState exact grade, temper, or heat-treat condition.
Inspection scopeMark dimensions or surfaces that must appear on reports.

If the part has sealing faces, bearing fits, visible front faces, or assembly datums, those should be labeled directly. A general note is rarely enough for those features.

Common notes buyers forget

  • deburr and edge-break requirements
  • thread depth or engagement note
  • cosmetic surface identification
  • masking zones for anodizing or coating
  • whether alternate material is acceptable
  • which dimensions must appear on the report

Materials, quantity, and timing notes change the quote

A drawing may define the part, but the RFQ still needs the commercial and manufacturing context that changes how a supplier quotes the job.

  • State the exact material grade you want quoted
  • Say whether alternates are allowed
  • List prototype quantity and expected repeat demand separately
  • State target delivery timing instead of leaving urgency implied
  • Include destination country if packaging or export documents matter

If the project may move into repeat supply, say that early. It affects fixture logic, finish sequencing, and whether the supplier should plan for prototype-to-production handoff instead of a one-off sample build.

Inspection and document requests

  • dimensional report for critical features
  • first article inspection for early production builds
  • material certificate or traceability record
  • certificate of conformity
  • finish verification or appearance standard
  • packaging separation or label requirements for mixed part numbers

Common RFQ mistakes that slow down quoting

3D file without controlled notesThe supplier sees geometry but not the tolerances, threads, or finish logic that control the quote.
Material family instead of grade“Stainless steel” or “aluminum” is often too broad to quote consistently.
No quantity patternOne prototype lot and an annual repeat program are not the same cost structure.
Inspection added too lateAdding CMM, FAI, or cert requests after quote approval forces rework.
Multiple active revisionsA supplier cannot quote confidently if the release version is unclear.
Undefined cosmetic requirementVisible faces and finish acceptance should be written, not assumed.

RFQ submission checklist

Before you send the package, confirm the supplier can see both the part definition and the business context that drives the quote.

  • 3D CAD model or native file
  • 2D drawing PDF with revision block
  • material grade and any compliance note
  • quantity, lot split, or forecast pattern
  • finish and cosmetic callouts
  • critical dimensions and thread details
  • requested inspection documents
  • target lead time
  • destination country
  • NDA requirement, if needed

Best next actions

Ready to submit Upload the full RFQ package
Need help on tolerances Review the tolerance guide
Need DFM cleanup Use the machining design guide
Need secure file transfer Open secure drawing upload

Frequently asked questions

For the most accurate quote, yes. The 3D model defines geometry quickly, while the 2D drawing controls tolerances, threads, finishes, and revision status.

You can usually get a rough feasibility review, but not a controlled quote comparison. A sample does not replace revision-controlled dimensions, finish notes, and tolerance callouts.

Use a general tolerance note for non-critical features and mark function-critical dimensions individually. Tight tolerances should be limited to the features that affect fit, sealing, alignment, or motion.

Yes. If you need a dimensional report, first article inspection, or material certificate, include that request before quoting so the supplier can price the scope correctly.

State the thread standard, size, class if needed, and depth or engagement requirement. If the thread is critical to assembly, mark it as a controlled feature on the drawing.

Call out both the finish type and the appearance expectation. If only one face is visible in the final assembly, identify that cosmetic zone directly on the drawing.

Send the RFQ package once, not in four clarification rounds

Bundle the drawing, CAD model, material, quantity, finish, tolerance, and document requirements together so quote review starts with the real scope of the job.