How to Create a High-Precision CNC Machining Scale Prototype?

1. Usinage pré-CNC: Design Preparation for Scale Prototypes

Avant de commencer Usinage CNC for the scale prototype, a thorough design stage is essential to meet functional and user needs. This stage follows a linear process with clear key points, Comme indiqué dans le tableau ci-dessous.

2. Core CNC Machining Process for Scale Prototypes

Le Processus d'usinage CNC is crucial for turning design drawings into physical scale prototype parts. It requires strict material preparation, step-by-step operation, and precision control to ensure the scale’s performance.

2.1 Préparation des matériaux: Selecting Suitable Base Materials

The choice of materials directly affects the scale’s quality, poids, and machining efficiency. The following table compares common materials:

2.2 Step-by-Step CNC Machining Execution

Follow this linear workflow to ensure machining precision:

1. Programmation & Planification des chemins: Use CAM software like Mastercam and PowerMill to generate tool paths. For ultra-thin housings, set up layer-by-layer milling to avoid deformation. Use large-diameter tools for roughing to remove excess material quickly and small-diameter tools for finishing to ensure surface smoothness.
2. Serrage & Positionnement: Fix plastic sheets with a vacuum cup to ensure stability during machining. Calibrate the center position to guarantee the symmetry of the scale prototype. For curved surface structures, use four-axis linkage processing to achieve accurate shaping.
3. Exécution d'usinage:

• Housing Processing: Mill the shell into the desired shape, retaining features such as display cutouts, keyholes, and sensor windows. Chamfer the edges (Par exemple, R2mm) to improve the grip and prevent scratches.
• Internal Structure Processing: Mill sensor mounting grooves with a depth tolerance of ±0.05mm to ensure the sensor is installed horizontally. Reserve fixing holes (Par exemple, M2 threads) in the circuit board slot for secure component installation.
• Metal Parts Processing: For sensor protective covers, perform finishing with a tolerance of ±0.02mm to ensure the flatness of the transparent window, which does not affect the sensor’s working performance.

4. Preliminary Surface Check: Après l'usinage, remove burrs from the parts and verify the positions of holes and the depth of grooves to ensure they meet design requirements before post-processing.

2.3 Critical Process Control

To avoid functional defects of the scale prototype, focus on the following two key controls:

• Contrôle de la tolérance: Strictly control the housing size tolerance within ±0.1mm to ensure the assembly of various components. The sensor mounting slot tolerance is controlled at ±0.05mm to ensure the sensor’s accurate installation and weighing precision.
• Surface Treatment Control: According to design requirements, perform frosting treatment on the shell to achieve a non-slip effect or high-gloss polishing to enhance the product’s texture, improving both usability and aesthetics.

3. Après l'achat: Traitement de surface & Assemblée

Après l'usinage CNC, reasonable surface treatment and correct assembly are essential to turn parts into a functional scale prototype.

3.1 Traitement de surface: Material-Specific Processes

Different materials require targeted surface treatment to improve performance and appearance:

3.2 Component Testing & Assembly Checklist

Ensure the scale prototype functions properly through the following testing and assembly steps:

• Vérification fonctionnelle:

1. Install load cells and test the weighing accuracy, requiring an error ≤±0.2kg to meet the scale’s measurement requirements.
2. Debug the display and buttons, checking the uniformity of the LED backlight to ensure clear weight display and sensitive button operation.

• Processus d'assemblage:

1. Attach the sensor, circuit board, and battery to the internal bracket, and connect the wires correctly to ensure stable electrical connections.
2. Assemble the housing and case cover using screws or snaps to ensure a tight seal, preventing dust from entering and affecting the internal components’ performance.
3. Equip the scale with non-slip foot pads (silicone material) to improve stability during use and avoid sliding on smooth surfaces.

4. Optimisation des prototypes & Itération

Based on user testing feedback and actual use conditions, optimize the scale prototype to improve its performance and user experience.

5. Common Technical Difficulties & Solutions

During the CNC machining and prototype production of the scale, the following technical difficulties may be encountered, and corresponding solutions are provided:

6. Livraison & Subsequent Applications

A well-made scale prototype has multiple uses and provides a reliable basis for subsequent mass production:

• Display Purpose: The prototype can be used for marketing activities (Par exemple, product exhibitions), customer proposals to demonstrate the product’s appearance and functions, and appearance verification to ensure the design meets market aesthetics.
• Data Inheritance: Collect and sort out CNC machining parameters (Par exemple, tool path settings, vitesse de coupe) and problem records (Par exemple, solutions to shell deformation) during the prototype production process, and feed them back to the mass production team. This helps optimize the injection mold or metal die-casting process, reducing production risks and improving production efficiency.

Point de vue de la technologie Yigu

À la technologie Yigu, nous croyons CNC machining is the core link in creating high-quality scale prototypes. It ensures that the prototype accurately restores the design intention, meets both functional and aesthetic needs. When producing scale prototypes, we focus on two key points: material selection that matches mass production standards (Par exemple, choosing ABS plastic for cost-effective housings and aluminum alloy for high-end parts) and strict control of machining precision (especially the sensor mounting slot tolerance to ensure weighing accuracy). By combining precise CNC machining with continuous prototype optimization, we help customers shorten the product development cycle and lay a solid foundation for mass production. À l'avenir, we will further integrate intelligent technologies into the CNC machining process to improve production efficiency while maintaining high precision.

FAQ

1. What factors affect the weighing accuracy of a CNC machined scale prototype, and how to ensure it?

The main factors include the accuracy of the sensor mounting position, the performance of the sensor itself, and the calibration of the circuit. Pour assurer la précision, use high-precision CNC machine tools to process the sensor groove and calibrate with a laser level; select high-quality load sensors; and debug the circuit to ensure the error is ≤±0.2kg.

2. Can the CNC machined scale prototype be directly used for mass production?

Non. The prototype is mainly used for design verification, tests fonctionnels, and market feedback collection. Pour la production de masse, it is necessary to optimize the production process (Par exemple, use injection molding for plastic housings instead of CNC machining) based on the prototype data to improve production efficiency and reduce costs.

3. How long does it take to produce a CNC machined scale prototype?

The production cycle depends on the design complexity. For a standard scale prototype (with a simple structure and common materials), it usually takes 7-10 jours, including design finalization, Usinage CNC, traitement de surface, et assemblage. Pour les prototypes avec des structures complexes (Par exemple, surfaces courbes, multiple sensors), the cycle may be extended to 12-15 jours.