Buyer guide
CNC machining RFQ checklist for custom precision manufacturing
A precision manufacturing RFQ should make the part, material, tolerance expectations and production stage clear. Complete inputs help the first reply move beyond basic file requests.
1. Part drawing and 3D files
For CNC machining and many custom parts, a complete drawing and a 3D model are the fastest way to start. If only one file is available, send it first and explain what is still missing.
- 2D PDF drawing
- STEP, STP, IGS or other 3D model
- Revision number
- Critical dimensions
- Assembly context if the part fits into a larger system
2. Material and grade
Material should be specific where possible. If the exact grade is not fixed, describe the application and mechanical or environmental requirement.
- Material type and grade
- Substitute material preference, if acceptable
- Strength, corrosion, weight or temperature requirements
- Any restricted material requirements
3. Tolerance and critical features
Not every dimension needs the tightest tolerance. Mark the critical features clearly so manufacturing review can focus on what affects function, fit or assembly.
- General tolerance standard, if used
- Critical-to-function dimensions
- Thread, hole, slot or mating features
- Flatness, concentricity or surface requirements, if relevant
- Inspection expectations
4. Surface finish and post-processing
Surface finish can change cost, lead time and supplier matching. Confirm whether the finish is functional, cosmetic or protective.
- Anodizing, plating, powder coating, polishing, passivation or other finish
- Color requirement
- Cosmetic surface expectations
- Masking areas
- Packaging protection for finished surfaces
5. Prototype, sample or repeat production
A prototype RFQ and a repeat-production RFQ should be reviewed differently. State the project stage clearly so sample, pilot and repeat-order expectations are not mixed together.
- Prototype quantity
- Sample approval requirement
- Trial order quantity
- Repeat-production estimate
- Target delivery destination
- Required timeline
First reply inputs
Send what is available now
Missing details can be identified during review. A useful first message should still show the application, quantity and delivery context.
- 2D drawing and available 3D files
- Material, grade and acceptable substitutes
- Critical dimensions and tolerance notes
- Surface finish and post-processing requirement
- Prototype or production quantity and destination