A useful CNC machining quotation starts with a clear part definition. The goal is not to create the longest possible RFQ; it is to give the manufacturing team enough information to understand the geometry, intended function, quantity and acceptance requirements. A complete package reduces assumptions and helps the supplier identify questions before production planning begins.
1. Send the current 3D model and 2D drawing
Provide the latest 3D model together with a dimensioned drawing when one is available. The model defines the part geometry, while the drawing can identify datums, tolerances, threads, surface finishes and notes that may not be contained in the model.
Use the same part number and revision on every file. If the model and drawing have different revision labels, state which one controls. Commonly accepted neutral model formats such as STEP or STP are useful for review, while a PDF drawing makes requirements easy to reference.
2. Identify the features that control part function
Not every dimension has the same importance. Explain which faces locate the component, which holes align with mating parts and where fits, sealing surfaces or assembly interfaces are involved. Marking critical features helps the manufacturing and inspection plans focus on the relationships that matter.
Avoid applying the tightest possible tolerance to every surface. Instead, distinguish functional tolerances from general dimensions and cosmetic requirements. If a flexible or thin-wall part must be inspected in a restrained condition, describe the fixture or assembly condition used for acceptance.
3. Specify material and final condition
State the material grade, temper or condition required by the design. Add any heat treatment, anodizing, plating, passivation, coating or cosmetic requirements. Identify surfaces that must remain free of coating and whether colour, texture or appearance is important.
If alternatives are acceptable, explain which properties must be preserved and who must approve a substitution. This is more useful than asking the supplier to guess whether an equivalent material is permitted.
4. Include quantity, schedule and repeat-order expectations
Provide the initial order quantity and indicate whether it is a prototype, pilot batch or repeat production requirement. If future volumes may change, share the expected range so the manufacturing route can be reviewed in context.
Give the required delivery target and any milestone that matters to your project. A requested date is not a confirmed lead time; it gives the supplier a basis for discussing material availability, process sequence and inspection workload.
5. Define inspection and documentation requirements
List the documents or measurements required with the shipment. Examples may include a dimensional report, material documentation, finish certification, first-article approval, marking or special packaging instructions. Requirements that affect acceptance should be included before quotation rather than introduced after the manufacturing plan has been agreed.
For complex housings and multi-face parts, specify the datum structure and the feature relationships that require verification. Learn more about our approach to CNC machining capabilities and made-to-drawing components.
CNC machining RFQ checklist
- Current 3D model and dimensioned drawing
- Matching part number and revision
- Material grade and final condition
- Critical features, datums and mating interfaces
- Prototype or batch quantity
- Requested delivery target
- Surface treatment and cosmetic requirements
- Inspection, documentation, marking and packaging requirements
What happens after you submit the RFQ?
The information is reviewed against the proposed manufacturing route. Questions about geometry, access, tolerances or inspection should be resolved before the quotation is treated as complete. This review does not replace your engineering approval, but it helps both parties work from the same part definition.
Send your drawings and RFQ details to MIGE Precision for an engineering review.