Developing a refrigerator prototype model requires a precise CNC machining process to validate design feasibility, test component fit, and evaluate aesthetic performance. Unlike small appliance prototypes, refrigerators have complex structures (Por exemplo, box, door body, refrigeration system mounts) that demand strict control over dimensional accuracy and surface quality. This guide breaks down the full workflow—from preliminary preparation to post-processing—with key parameters, material selections, and practical tips to ensure prototype success.
1. Preparação Preliminar: Estabeleça a base para a usinagem
The success of CNC machining starts with thorough preparation, including 3D modeling, Seleção de material, and equipment/tool readiness. This stage ensures the subsequent process is efficient and error-free.
(1) 3D Modelagem: Define Prototype Details with Precision
Use o software CAD profissional (Por exemplo, SolidWorks, e) to create a detailed 3D model that covers all critical structures of the refrigerator. The model must balance design requirements, assembly logic, and machining feasibility.
| Structure Category | Key Design Details | Requisitos de precisão | Propósito |
| Main Body (Box) | Inner cavity size (Por exemplo, 500mm×600mm×1800mm), partition slots, refrigeration system mounting holes | Cavity dimension error ±0.2mm; hole position tolerance ±0.1mm | Ensure fit for insulation layers and refrigeration components |
| Corpo da porta | Frame size, observation window cutout (se aplicável), hinge mounting slots | Frame parallelism error ≤0.1mm; cutout edge smoothness Ra ≤1.6μm | Guarantee tight sealing when closed; match hinge assembly |
| Functional Components | Handle shape (curva ergonômica), control panel slot, drawer slide rails | Handle surface roughness Ra ≤0.8μm; slot depth tolerance ±0.05mm | Improve user experience; ensure smooth operation of moving parts |
Model Optimization Tips:
- Layered Design: Split complex structures (Por exemplo, door body with inner liner) into separate machinable components to avoid tool interference. Por exemplo, machine the door frame and inner liner separately, then assemble them.
- Process Marking: Label key machining features (Por exemplo, “no tool marks on visible surfaces”) and reference datums (Por exemplo, box bottom as the origin) to guide CNC programming.
- Interference Check: Use software to simulate component assembly (Por exemplo, door closing, drawer sliding) and eliminate overlapping or collision risks (Por exemplo, ensure 2–3mm clearance between door and box).
(2) Seleção de material: Match Performance to Component Roles
Different parts of the refrigerator prototype require materials with specific properties (Por exemplo, força, transparência, lustro). Below is a detailed comparison of suitable options:
| Tipo de material | Applicable Parts | Propriedades -chave | Machinability Advantages |
| Plástico ABS | Box body, door frame, lidar | Boa resistência ao impacto (Izod impact strength 20 KJ /), fácil de colorir, baixo custo | Low tool wear; can be machined at high speed (10,000–15,000 rpm) |
| PC Plástico | Observation window, control panel cover | Alta transparência (light transmittance ≥88%), resistente ao impacto (10x mais forte que o vidro) | Precision cutting achievable; minimal chipping on edges |
| Acrílico (PMMA) | Exterior decorative strips, logo plates | Excellent gloss (60° gloss value ≥90%), vivid color expression | Smooth surface after polishing; suitable for aesthetic-focused parts |
| Liga de alumínio (6061) | Drawer slide rails, refrigeration mounts | Alta rigidez (resistência à tracção 276 MPA), boa resistência à corrosão | Velocidade de usinagem rápida; suitable for load-bearing structural parts |
Material Blank Preparation:
- Cut blanks according to the maximum size of each part, reserving 5–10mm machining allowance on all sides. Por exemplo:
- A door frame with a final size of 600mm×800mm×50mm requires a 610mm×810mm×60mm ABS blank.
- An aluminum alloy slide rail (100mm×20mm×5mm) needs a 110mm×30mm×15mm blank to accommodate roughing and finishing.
(3) Equipamento & Preparação de ferramentas: Ensure Machining Accuracy
Select CNC equipment and tools based on material properties and part complexity to avoid defects like tool marks or dimensional deviations.
| Equipment/Tool Type | Selection Criteria | Recommended Specifications |
| CNC Machining Center | High-precision 3-axis or 5-axis models (for curved surfaces like door handles) | Positioning accuracy ±0.005mm; spindle speed range 8,000–24,000 rpm |
| Cortadores de moagem | Solid carbide tools for plastic; Aço de alta velocidade (HSS) tools for aluminum alloy | – Plástico: Φ6–Φ12mm flat-bottom mills (para desbaste), Φ3–Φ6mm ball-head mills (para acabamento)- Alumínio: Φ8–Φ16mm end mills (para desbaste), Φ4–Φ8mm face mills (para superfícies planas) |
| Exercícios & Taps | Twist drills for holes; machine taps for threaded mounting holes | – Exercícios: Φ2–Φ10mm (match hole size requirements)- Taps: M3–M8 (for hinge and handle mounting) |
| Acessórios | Vacuum suction cups (for flat plastic parts); precision vises (para componentes de alumínio) | Vacuum pressure ≥0.8 MPa; vise clamping force ≥5 kN to prevent workpiece displacement |
2. Programação & Configurar: Translate Design to Machinable Code
This stage converts the 3D model into actionable CNC instructions and prepares the machine for operation—critical for ensuring machining accuracy.
(1) Programação de came: Generate Machining Code
Use o software CAM (Por exemplo, MasterCam, PowerMill) Para converter o modelo 3D em código G, and optimize parameters based on material and part structure.
| Estágio de usinagem | Parâmetros -chave | Dicas de otimização |
| Desbaste | – Velocidade de corte: 10,000–12,000 rpm (Abs); 12,000–15,000 rpm (alumínio)- Taxa de alimentação: 1,000–1.500 mm/min (Abs); 800–1,200 mm/min (alumínio)- Cutting depth: 2–5mm (Abs); 1-3mm (alumínio) | Usar “corte em camadas” to remove 90% de excesso de material; leave 0.3–0.5mm allowance for finishing |
| Acabamento | – Velocidade de corte: 15,000–18,000 rpm (Abs); 18,000–22,000 rpm (alumínio)- Taxa de alimentação: 500–800 mm/min (Abs); 400–600 mm/min (alumínio)- Cutting depth: 0.1-0,3mm | Para superfícies curvas (Por exemplo, lidar), usar “spiral cutting” with a step distance of 0.05mm to eliminate tool marks |
| Hole Machining | – Drilling speed: 8,000–10,000 rpm- Tapping speed: 500–800 rpm (M3–M5 taps) | Usar “pecking drilling” (drill 3mm, retract 1mm) to clear chips; apply cutting fluid for aluminum to prevent thread stripping |
(2) Configuração da máquina: Install Tools & Secure Workpieces
Proper setup ensures the machine, ferramentas, and workpieces are aligned to the same coordinate system—avoiding dimensional errors.
Instalação da ferramenta & Calibração:
- Mount tools into the tool magazine and use a tool setter to measure tool length and radius. Record data in the CNC system to compensate for tool wear.
- Por exemplo: A Φ6mm ball-head mill for ABS finishing needs its length calibrated to ±0.001mm to ensure consistent cutting depth.
Panificação da peça de trabalho:
- Clean the machining table to remove debris, then fix the blank using fixtures:
- For ABS box blanks: Use vacuum suction cups to cover 80% of the blank’s bottom surface (prevents warping during machining).
- For aluminum slide rails: Secure with a precision vise, ensuring the blank is parallel to the table (error ≤0.01mm).
- Set the workpiece origin (Por exemplo, use a touch probe to detect the blank’s edge) and input coordinates into the CNC system.
3. Execução de usinagem CNC: From Blank to Prototype Structure
This stage divides machining into roughing and finishing to balance efficiency and precision—critical for complex refrigerator structures.
(1) Desbaste: Moldar a fundação do protótipo
Roughing removes most excess material to bring the blank close to the final shape, prioritizing speed while avoiding tool damage.
| Tipo de componente | Roughing Focus | Operações-chave & Parâmetros |
| Refrigerator Box | Machine outer frame and inner cavity; mill partition slots | Use Φ12mm flat-bottom mill (Abs); velocidade de corte 11,000 RPM, taxa de alimentação 1,200 mm/min; cavity depth cut in 3 passes (5mm each) |
| Corpo da porta | Mill door frame and observation window cutout; machine hinge mounting slots | Use Φ10mm end mill (Abs); velocidade de corte 10,000 RPM, taxa de alimentação 1,000 mm/min; cutout edges left with 0.3mm finishing allowance |
| Aluminum Slide Rails | Machine rail profile and mounting holes | Use Φ8mm end mill (alumínio); velocidade de corte 14,000 RPM, taxa de alimentação 1,000 mm/min; holes pre-drilled with Φ3mm twist drill |
Post-Roughing Inspection:
- Use a digital caliper to check key dimensions (Por exemplo, box cavity size, door frame width) and ensure they are within ±0.5mm of the design value.
- Clean chips from the workpiece surface with compressed air to avoid interfering with finishing.
(2) Acabamento: Achieve Precision & Qualidade da superfície
Finishing refines the workpiece to meet final design requirements, focusing on dimensional accuracy and surface smoothness.
| Tipo de componente | Finishing Focus | Operações-chave & Parâmetros |
| Box Inner Cavity | Smooth cavity walls and partition slot edges; ensure flatness of mounting surfaces | Use Φ6mm ball-head mill (Abs); velocidade de corte 16,000 RPM, taxa de alimentação 600 mm/min; wall roughness Ra ≤1.6μm |
| Door Observation Window | Smooth cutout edges; ensure parallelism with door frame | Use Φ3mm ball-head mill (computador); velocidade de corte 18,000 RPM, taxa de alimentação 500 mm/min; edge chipping ≤0.1mm |
| Lidar | Polish curved surface; machine ergonomic grip contour | Use Φ4mm ball-head mill (Abs); velocidade de corte 17,000 RPM, taxa de alimentação 700 mm/min; surface roughness Ra ≤0.8μm |
Finishing Quality Checks:
- Use a surface roughness tester to verify Ra values (Por exemplo, visible surfaces require Ra ≤0.8μm).
- Use uma máquina de medição de coordenadas (Cmm) to inspect critical features: Por exemplo, hinge mounting holes must have a position error ≤0.1mm to ensure door alignment.
4. Pós-processamento: Enhance Prototype Performance & Estética
Post-processing improves the prototype’s appearance, funcionalidade, and durability—bridging the gap between machined parts and a realistic refrigerator model.
(1) Tratamento de superfície: Refine Texture & Aparência
Tailor treatment methods to material type and part function:
| Material/Part Type | Etapas de tratamento de superfície | Resultado Esperado |
| Caixa ABS/corpo da porta | 1. Areia com 400# → 800# → 1200# lixa (remover marcas de ferramentas)2. Limpe com álcool isopropílico (desengordurar)3. Spray de tinta fosca (50espessura de μm, design de correspondência de cores) | Adesão da pintura ≥4B (Sem descascamento); brilho superficial 30–50 GU (acabamento fosco) |
| Janela de observação do PC | 1. Polonês com 600# pasta abrasiva (remover marcas de corte)2. Polonês com 1200# colar (aumentar a transparência)3. Limpe com limpador de lentes | Transmitância de luz ≥85%; sem arranhões visíveis ou neblina |
| Tiras Decorativas Acrílicas | 1. Areia com 1000# lixa (Bordas suaves)2. Polir com pasta de polimento específica para acrílico3. Aplicar revestimento protetor UV | Valor de brilho ≥90 GU; sem amarelecimento depois 100 horas de exposição UV |
| Aluminum Slide Rails | 1. Desengordure com limpador alcalino2. Anodizar (formar filme de óxido cinza prateado de 8–10μm)3. Jateamento de areia (superfície fosca) | Resistência à corrosão: Sem ferrugem após teste de névoa salina de 48 horas; coeficiente de atrito ≤0,15 |
(2) Conjunto & Depuração: Validate Prototype Functionality
Monte componentes usinados e teste funções-chave para garantir que o protótipo atenda aos objetivos do projeto:
Etapas de montagem:
- Verificação pré-montagem: Verifique se todas as peças atendem aos requisitos dimensionais (Por exemplo, a moldura da porta se ajusta ao corpo da caixa com folga de 2–3 mm).
- Instalação de componentes:
- Monte dobradiças na porta e na caixa (use uma chave de torque para aplicar uma força de 5–8 N·m para evitar danos à rosca).
- Instale a maçaneta na porta (ensure alignment; no wobble when pulled).
- Attach slide rails to drawers and box (test sliding resistance ≤5N).
- Sealing Test: Place a thin paper strip between door and box, close the door, and pull the strip—resistance should be uniform (indicates tight sealing).
Functional Debugging:
- Door Operation: Test opening/closing 100 times—door should stay closed without manual locking; no squeaking.
- Drawer Sliding: Open/close drawers 50 times—no jamming; slides smoothly throughout the stroke.
- Component Fit: Check that simulated refrigeration system mounts (Por exemplo, compressor brackets) align with holes (position error ≤0.1mm).
5. Controle de qualidade & Otimização: Ensure Prototype Reliability
Strict quality control identifies defects early, while optimization reduces costs and improves efficiency for future iterations.
(1) Key Quality Control Standards
| Control Item | Acceptance Criteria | Inspection Method |
| Precisão dimensional | – Box cavity: ± 0,2 mm- Door frame: ± 0,1 mm- Hole position: ± 0,1 mm | Cmm (para recursos críticos); PALIPER DIGITAL (para dimensões gerais) |
| Qualidade da superfície | – Visible surfaces: RA ≤0,8μm, no tool marks/scratches- Hidden surfaces: RA ≤1,6μm | Surface roughness tester; Inspeção visual (under 500lux light) |
| Assembly Fit | – Door-box clearance: 2-3mm (uniforme)- Drawer sliding resistance: ≤5N | Feeler gauge (for clearance); force gauge (for sliding resistance) |
| Material Performance | – ABS impact resistance: ≥15 kJ/m²- PC transparency: ≥85% | Izod impact tester; spectrophotometer |
(2) Process Optimization Tips
- Material Saving: Para peças grandes (Por exemplo, box body), design hollow structures (with 3–5mm thick walls) to reduce blank size—saves 20–30% material cost.
- Eficiência de usinagem: Combine roughing and semi-finishing for simple parts (Por exemplo, decorative strips) to reduce tool change time by 15–20%.
- Post-Processing Simplification: For non-visible parts (Por exemplo, inner partition slots), skip painting—saves 10–15% of post-processing time.
Yigu Technology’s Perspective on CNC Machining Refrigerator Prototype Models
Na tecnologia Yigu, acreditamos design-machining integration is the core of efficient refrigerator prototype development. Many clients face issues like door sealing failure or drawer jamming due to disconnected design and machining. Our team optimizes models for manufacturability: Por exemplo, we add 0.3mm machining allowance to door frames to ensure sealing clearance, and design self-lubricating structures for slide rails to reduce post-processing. We also select materials strategically—using ABS for main bodies (econômico, easy to finish) and PC for observation windows (alta transparência, resistente ao impacto). For large-batch prototypes, we use multi-cavity fixtures to machine 2–3 parts at once, Cortando o tempo de produção por 40%. Our goal is to deliver prototypes that accurately reflect mass-production effects, helping clients shorten product development cycles by 25–30%.