When sourcing custom CNC machined parts, the quality of your Request for Quotation (RFQ) can significantly affect pricing accuracy, lead time, and manufacturing quality. An incomplete RFQ may lead to repeated clarification emails, unexpected costs, production delays, or parts that do not meet your requirements.
Whether you need a few prototypes or thousands of precision CNC machined parts, providing clear and complete information helps your manufacturing supplier understand the project and prepare an accurate quotation.
In this guide, we explain what to include in a CNC machining RFQ, how to avoid common mistakes, and how to make the quotation process more efficient.
What Is a CNC Machining RFQ?
An RFQ, or Request for Quotation, is a document or package of information sent to a manufacturing supplier to request pricing, lead time, and production details for custom parts.
A typical CNC machining RFQ includes engineering drawings, 3D CAD files, material specifications, order quantities, tolerances, surface finish requirements, and delivery expectations.
The more complete your RFQ is, the easier it is for a supplier to evaluate manufacturing feasibility, estimate production costs, and identify potential design issues before production begins.
Provide 2D Engineering Drawings
A clear 2D engineering drawing is one of the most important parts of a CNC machining RFQ. Your drawing should include:
Not every dimension needs an extremely tight tolerance. Apply tighter tolerances only where functional requirements justify them. If certain dimensions are especially important for assembly or performance, identify them clearly on the drawing.
Include 3D CAD Files
A 3D CAD model helps the supplier understand the complete geometry of your part, including pockets, curved surfaces, complex profiles, and internal features. Commonly used formats include STEP and IGES.
For the best results, provide both the 3D model and the 2D drawing. If the two files conflict, clearly state which document takes precedence. Before sending, confirm they represent the same design revision.
Specify the Material
6061 (general) or 7075 (high strength).
304 and 316 for corrosion resistance.
Structural and mechanical applications.
POM, Nylon for low-friction/insulation.
If material certification, traceability, or a specific standard is required, state this in the RFQ. Avoid broad categories when the exact grade affects compliance.
5. State the Required Quantity
Include initial order quantity and expected annual demand. Pricing differs significantly between Prototypes (1-10), Small Batches (10-100), and Large Production (1000+).
6. Define Tolerances & Critical Features
Identify general tolerances and tighter limits for critical features. A tolerance should reflect the part’s actual functional requirements to avoid unnecessary costs.
7. Specify Surface Finish and Post-Processing
Common options include Anodizing, Bead blasting, Powder coating, Plating, Polishing, and Silkscreen printing.
Note: Identify critical dimensions that must be maintained after finishing, as treatments can change final dimensions.
✔ 8. Heat Treatment
Specify hardness range, treatment standards, RoHS/REACH compliance, or special packaging needs. Don’t assume these are included automatically.
✔ 9. Quality Documentation
Clarify if you need First Article Inspection (FAI), CMM reports, or material certificates. Defining this early helps the supplier estimate correct effort.
✔ 10. Packaging & Delivery
Include delivery dates, shipping destination, and preferred methods. Specify protection for delicate surfaces to prevent damage during transit.
✔ 11. Protect Designs (NDA)
Communicate NDA requirements before sharing sensitive files. Identify the correct technical contact to prevent communication delays.
12. How Better RFQs Lead to Better Quotes
A complete RFQ allows for meaningful comparisons of price, lead time, and quality. The cheapest quote is not always the best; look for reliability and technical clarity.
CNC Machining RFQ Checklist
- ✓ 2D engineering drawing
- ✓ 3D CAD file
- ✓ Material grade
- ✓ Order quantity
- ✓ Surface finish
- ✓ Heat treatment
- ✓ Inspection docs
- ✓ Packaging info
- ✓ Delivery date
- ✓ NDA requirements
Work with HY Metals on Your Custom CNC Machining Project
At HY Metals, we support custom manufacturing through CNC milling, turning, multi-axis machining, and sheet metal fabrication. Our engineering team reviews your drawings to identify concerns before production begins.
Send HY Metals your files for a professional review:
susanx@hymetalproducts.com
Post time: Oct-23-2026