How to Efficiently Get Quotes for Custom Brass CNC Machined Parts?

— Complete Checklist & Key Considerations

When requesting quotes for custom brass CNC machined parts, providing clear and comprehensive technical/commercial information is crucial for receiving accurate pricing and ensuring smooth production. Below are the details you need to prepare:

1. Drawings (2D/3D): The Foundation of Technical Requirements

- Mandatory drawings:

- 3D models (Recommended): Submit in STP, STEP, or IGES formats to visualize complex geometries and minimize misinterpretation.

- 2D engineering drawings (Essential): Include critical dimensions, datums, machining reference points, and specify projection method (e.g., Third Angle/First Angle).

- Key annotations:

- Clearly mark inspection-critical vs. reference dimensions (avoid over-dimensioning).

- Highlight special features (thin walls, deep holes, sharp edges).

2. Brass Material: Impacts Machinability and Cost

- Specify alloy grade: Common choices include C36000 (free-cutting brass) or C26000 (cartridge brass).

- Additional requirements:

- Material certifications needed? (RoHS, MSDS)

- Accept alternative alloys? (e.g., C37700 if C36000 is unavailable)

3. Quantity: Determines Pricing Strategy

- Define volume ranges:

- Prototype: 5-10 pcs

- Pilot batch: 100-500 pcs

- Annual forecast: e.g., 10,000 pcs/year

- Volume-based pricing:

- Low volume: Higher per-unit cost (setup/programming amortization).

- High volume: Optimized pricing available (confirm MOQ).

4. Surface Treatment: Functional & Aesthetic Needs

| Treatment | Application | Specifications |

| Electroplating (Ni/Cr) | Corrosion/wear resistance | State thickness (e.g., 8μm) |

| Passivation | Oxidation resistance | Avoid post-treatment welding |

| Sandblasting/Polishing | Aesthetics & deburring | Surface roughness (e.g., Ra0.8) |

- Special requests: Laser engraving, anodizing (confirm brass compatibility).

5. Technical Specifications: Prevent Hidden Costs

- Tolerances:

- Standard: ISO 2768-m for non-critical dimensions.

- Tight tolerances: ±0.02mm (increases inspection costs).

- Threads/holes:

- Specifications (M6×1, UNC 1/4-20), through/blind holes, tapping accuracy.

- Testing requirements:

- Full dimensional report (FAI), pressure test, salt spray test.

- Packaging:

- Anti-tarnish methods (vacuum sealing + VCI paper), shelf life.

6. Supplementary Information: Streamline Responses

- Target price range: Helps suppliers optimize processes (e.g., multi-axis machining).

- Lead time expectations:

- Prototype: 7 days

- Production: Weekly deliveries

- Supplier capabilities:

- Require DFM (Design for Manufacturing) analysis?

- Accept phased payments? (30% deposit + 70% balance)

Key Strategies to Avoid Quotation Delays

1. Provide standardized drawings: Avoid hand sketches/ambiguous descriptions.

2. Quantify requirements: Specify exact quantities, materials, deadlines.

3. Disclose hidden requirements: Operating environment (high temperature/humidity), industry certifications (medical/military).

By preparing this information, you’ll receive faster and more accurate quotes while reducing post-quote clarifications. Prioritize suppliers offering free DFM analysis to optimize designs and costs.

Start Your Brass CNC Project Today:

Visit http://www.selectionhardware.com or email alice@selectionsz.com