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 (PER ESEMPIO., box, door body, refrigeration system mounts) che richiedono un controllo rigoroso sulla precisione dimensionale e sulla qualità della superficie. Questa guida analizza l'intero flusso di lavoro, dalla preparazione preliminare alla post-elaborazione, con parametri chiave, selezioni dei materiali, e consigli pratici per garantire il successo del prototipo.
1. Preparazione preliminare: Gettare le basi per la lavorazione
The success of CNC machining starts with thorough preparation, including 3D modeling, Selezione del materiale, and equipment/tool readiness. This stage ensures the subsequent process is efficient and error-free.
(1) 3D Modellazione: Definisci i dettagli del prototipo con precisione
Usa il software CAD professionale (PER ESEMPIO., 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 | Requisiti di precisione | Scopo |
| Main Body (Box) | Inner cavity size (PER ESEMPIO., 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 |
| Door Body | Frame size, observation window cutout (se applicabile), 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 (ergonomic curve), 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 |
Suggerimenti per l'ottimizzazione del modello:
- Layered Design: Split complex structures (PER ESEMPIO., door body with inner liner) into separate machinable components to avoid tool interference. Per esempio, machine the door frame and inner liner separately, then assemble them.
- Process Marking: Label key machining features (PER ESEMPIO., “no tool marks on visible surfaces”) and reference datums (PER ESEMPIO., box bottom as the origin) to guide CNC programming.
- Interference Check: Use software to simulate component assembly (PER ESEMPIO., door closing, drawer sliding) and eliminate overlapping or collision risks (PER ESEMPIO., ensure 2–3mm clearance between door and box).
(2) Selezione del materiale: Abbina le prestazioni ai ruoli dei componenti
Different parts of the refrigerator prototype require materials with specific properties (PER ESEMPIO., forza, trasparenza, lucentezza). Below is a detailed comparison of suitable options:
| Tipo di materiale | Applicable Parts | Proprietà chiave | Machinability Advantages |
| Plastica addominali | Box body, door frame, maniglia | Buona resistenza all'impatto (Izod impact strength 20 KJ /), facile da colorare, basso costo | Low tool wear; can be machined at high speed (10,000–15,000 rpm) |
| Plastica per PC | Observation window, control panel cover | Elevata trasparenza (light transmittance ≥88%), resistente all'impatto (10x più forte del vetro) | Precision cutting achievable; minimal chipping on edges |
| Acrilico (PMMA) | Exterior decorative strips, logo plates | Excellent gloss (60° gloss value ≥90%), vivid color expression | Smooth surface after polishing; suitable for aesthetic-focused parts |
| Lega di alluminio (6061) | Drawer slide rails, refrigeration mounts | Alta rigidità (resistenza alla trazione 276 MPA), Buona resistenza alla corrosione | Velocità di lavorazione rapida; suitable for load-bearing structural parts |
Preparazione del materiale grezzo:
- Cut blanks according to the maximum size of each part, reserving 5–10mm machining allowance on all sides. Per esempio:
- 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) Attrezzatura & Preparazione degli strumenti: Garantire la precisione della lavorazione
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 |
| Fresate | Solid carbide tools for plastic; acciaio ad alta velocità (HSS) tools for aluminum alloy | – Plastica: Φ6–Φ12mm flat-bottom mills (per laalpantina), Φ3–Φ6mm ball-head mills (per finire)- Alluminio: Φ8–Φ16mm end mills (per laalpantina), Φ4–Φ8mm face mills (per superfici piatte) |
| Esercitazioni & Taps | Twist drills for holes; machine taps for threaded mounting holes | – Esercitazioni: Φ2–Φ10mm (match hole size requirements)- Taps: M3–M8 (for hinge and handle mounting) |
| Infissi | Vacuum suction cups (for flat plastic parts); precision vises (for aluminum components) | Vacuum pressure ≥0.8 MPa; vise clamping force ≥5 kN to prevent workpiece displacement |
2. Programmazione & Impostare: Traduci il progetto in codice lavorabile
This stage converts the 3D model into actionable CNC instructions and prepares the machine for operation—critical for ensuring machining accuracy.
(1) Programmazione di cam: Genera codice di lavorazione
Usa il software CAM (PER ESEMPIO., Mastercam, PowerMill) Per convertire il modello 3D in code G, and optimize parameters based on material and part structure.
| Stadio di lavorazione | Parametri chiave | Suggerimenti di ottimizzazione |
| Ruvido | – Velocità di taglio: 10,000–12,000 rpm (Addominali); 12,000–15,000 rpm (alluminio)- Velocità di alimentazione: 1,000–1.500 mm/min (Addominali); 800–1,200 mm/min (alluminio)- Profondità di taglio: 2–5mm (Addominali); 1-3 mm (alluminio) | Utilizzo “taglio a strati” to remove 90% di materiale in eccesso; leave 0.3–0.5mm allowance for finishing |
| Finitura | – Velocità di taglio: 15,000–18,000 rpm (Addominali); 18,000–22,000 rpm (alluminio)- Velocità di alimentazione: 500–800 mm/min (Addominali); 400–600 mm/min (alluminio)- Profondità di taglio: 0.1-0,3 mm | Per superfici curve (PER ESEMPIO., maniglia), utilizzo “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) | Utilizzo “pecking drilling” (drill 3mm, retract 1mm) to clear chips; apply cutting fluid for aluminum to prevent thread stripping |
(2) Configurazione della macchina: Install Tools & Secure Workpieces
Proper setup ensures the machine, utensili, and workpieces are aligned to the same coordinate system—avoiding dimensional errors.
Installazione degli strumenti & Calibrazione:
- 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.
- Per esempio: A Φ6mm ball-head mill for ABS finishing needs its length calibrated to ±0.001mm to ensure consistent cutting depth.
Splegamento del pezzo:
- 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 (PER ESEMPIO., use a touch probe to detect the blank’s edge) and input coordinates into the CNC system.
3. Esecuzione di lavorazione a 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) Ruvido: Modellare la fondazione prototipo
Roughing removes most excess material to bring the blank close to the final shape, prioritizing speed while avoiding tool damage.
| Tipo di componente | Roughing Focus | Operazioni chiave & Parametri |
| Refrigerator Box | Machine outer frame and inner cavity; mill partition slots | Use Φ12mm flat-bottom mill (Addominali); velocità di taglio 11,000 RPM, velocità di alimentazione 1,200 mm/min; cavity depth cut in 3 passa (5mm each) |
| Door Body | Mill door frame and observation window cutout; machine hinge mounting slots | Use Φ10mm end mill (Addominali); velocità di taglio 10,000 RPM, velocità di alimentazione 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 (alluminio); velocità di taglio 14,000 RPM, velocità di alimentazione 1,000 mm/min; holes pre-drilled with Φ3mm twist drill |
Post-Roughing Inspection:
- Use a digital caliper to check key dimensions (PER ESEMPIO., 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) Finitura: Ottieni precisione & Qualità della superficie
Finishing refines the workpiece to meet final design requirements, focusing on dimensional accuracy and surface smoothness.
| Tipo di componente | Finishing Focus | Operazioni chiave & Parametri |
| Box Inner Cavity | Smooth cavity walls and partition slot edges; ensure flatness of mounting surfaces | Use Φ6mm ball-head mill (Addominali); velocità di taglio 16,000 RPM, velocità di alimentazione 600 mm/min; wall roughness Ra ≤1.6μm |
| Door Observation Window | Smooth cutout edges; ensure parallelism with door frame | Use Φ3mm ball-head mill (PC); velocità di taglio 18,000 RPM, velocità di alimentazione 500 mm/min; edge chipping ≤0.1mm |
| Handle | Polish curved surface; machine ergonomic grip contour | Use Φ4mm ball-head mill (Addominali); velocità di taglio 17,000 RPM, velocità di alimentazione 700 mm/min; surface roughness Ra ≤0.8μm |
Finishing Quality Checks:
- Use a surface roughness tester to verify Ra values (PER ESEMPIO., visible surfaces require Ra ≤0.8μm).
- Usa una macchina di misurazione delle coordinate (CMM) to inspect critical features: Per esempio, hinge mounting holes must have a position error ≤0.1mm to ensure door alignment.
4. Post-elaborazione: Enhance Prototype Performance & Estetica
Post-processing improves the prototype’s appearance, funzionalità, and durability—bridging the gap between machined parts and a realistic refrigerator model.
(1) Trattamento superficiale: Refine Texture & Aspetto
Tailor treatment methods to material type and part function:
| Material/Part Type | Surface Treatment Steps | Risultato atteso |
| ABS Box/Door Body | 1. Sand with 400# → 800# → 1200# carta vetrata (remove tool marks)2. Wipe with isopropyl alcohol (degrease)3. Spray matte paint (50μm thickness, color matching design) | Paint adhesion ≥4B (Nessun peeling); surface gloss 30–50 GU (finitura opaca) |
| PC Observation Window | 1. Polish with 600# abrasive paste (remove cutting marks)2. Polish with 1200# paste (enhance transparency)3. Clean with lens cleaner | Light transmittance ≥85%; no visible scratches or haze |
| Acrylic Decorative Strips | 1. Sand with 1000# carta vetrata (bordi lisci)2. Polish with acrylic-specific polishing paste3. Apply UV protective coating | Gloss value ≥90 GU; no yellowing after 100 hours of UV exposure |
| Aluminum Slide Rails | 1. Degrease with alkaline cleaner2. Anodize (form 8–10μm silver-gray oxide film)3. Sandblast (superficie opaca) | Resistenza alla corrosione: No rust after 48-hour salt spray test; friction coefficient ≤0.15 |
(2) Assemblaggio & Debug: Validate Prototype Functionality
Assemble machined components and test key functions to ensure the prototype meets design goals:
Passi di montaggio:
- Pre-Assembly Check: Verify that all parts meet dimensional requirements (PER ESEMPIO., door frame fits box body with 2–3mm clearance).
- Component Installation:
- Mount hinges to door and box (use torque wrench to apply 5–8 N·m force to avoid thread damage).
- Install handle onto door (ensure alignment; no wobble when pulled).
- Attach slide rails to drawers and box (test sliding resistance ≤5N).
- Prova di tenuta: 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 (PER ESEMPIO., compressor brackets) align with holes (position error ≤0.1mm).
5. Controllo di qualità & Ottimizzazione: Garantire l'affidabilità del prototipo
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 |
| Precisione dimensionale | – Box cavity: ± 0,2 mm- Door frame: ± 0,1 mm- Hole position: ± 0,1 mm | CMM (per caratteristiche critiche); calibro digitale (per dimensioni generali) |
| Qualità della superficie | – Visible surfaces: RA ≤0,8μm, no tool marks/scratches- Hidden surfaces: RA ≤1,6μm | Tester di rugosità superficiale; ispezione visiva (under 500lux light) |
| Assembly Fit | – Door-box clearance: 2-3 mm (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: Per gran parte (PER ESEMPIO., box body), design hollow structures (with 3–5mm thick walls) to reduce blank size—saves 20–30% material cost.
- Efficienza di lavorazione: Combine roughing and semi-finishing for simple parts (PER ESEMPIO., decorative strips) to reduce tool change time by 15–20%.
- Post-Processing Simplification: For non-visible parts (PER ESEMPIO., inner partition slots), skip painting—saves 10–15% of post-processing time.
Yigu Technology’s Perspective on CNC Machining Refrigerator Prototype Models
Alla tecnologia Yigu, Crediamo 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: Per esempio, 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 (economico, easy to finish) and PC for observation windows (elevata trasparenza, resistente all'impatto). For large-batch prototypes, we use multi-cavity fixtures to machine 2–3 parts at once, tagliare i tempi di produzione da 40%. Our goal is to deliver prototypes that accurately reflect mass-production effects, helping clients shorten product development cycles by 25–30%.