Processing porous prototype models in CNC is a key link in product development, widely used in automotive parts, enclos électroniques, et prototypage des dispositifs médicaux. Mastering the skills to process porous prototype models in CNC can ensure the accuracy of hole positions, reduce material waste, and speed up the prototype verification cycle. This article will explain the whole process in detail and provide practical solutions to common problems.
1. Design and Programming: Mettre les bases de la précision
The first step to process porous prototype models in CNC is to complete scientific design and accurate programming—this directly affects the final hole position accuracy and machining efficiency.
Specific Operations
- Use professional Logiciel CAO (comme Solidworks, Autocad) to design the 3D model of the porous prototype. During the design, pay special attention to the spacing between holes, hole depth, and the connection between holes and other structures to avoid design conflicts.
- Import the 3D model into Logiciel CAM (comme mastercam, et). The software will automatically generate CNC code, which clearly defines important parameters such as drilling position (coordinates of each hole), drilling depth (Par exemple, 5mm for through-holes, 3mm for blind holes), vitesse de broche (varie selon le matériau), and machining sequence (usually from shallow to deep, from edge to center).
Cas: When processing a porous aluminum alloy electronic enclosure prototype, engineers used SolidWorks to design 20 M3 threaded holes (hole depth 8mm, hole spacing 15mm). After importing into Mastercam, the CAM software generated code that set the machining sequence to start from the four corner holes and then process the middle holes, effectively avoiding material deformation caused by uneven stress.
2. Material and Tool Selection: Match Requirements for Efficiency
Choosing the right materials and tools is a prerequisite for smooth processing of porous prototype models in CNC. Improper selection will lead to problems such as tool breakage and unqualified hole quality.
Guide de sélection des matériaux
| Type de matériau | Avantages | Suitable Prototype Scenarios | Difficulté d'usinage |
| Plastique abs | Light weight, faible coût, Facile à machine | Low-load structural prototypes (Par exemple, enclos en plastique) | Faible |
| Plastique PC | Résistance à l'impact élevé, résistance à la chaleur | Prototypes for high-temperature environments (Par exemple, automotive instrument panels) | Moyen |
| Alliage en aluminium (6061) | Bonne rigidité, bonne conductivité thermique | High-precision structural prototypes (Par exemple, pièces mécaniques) | Faible |
| Acier inoxydable (304) | Résistance à la corrosion, forte résistance | Prototypes for harsh environments (Par exemple, dispositifs médicaux) | Haut |
Tool Selection Tips
- For plastic materials (Abs, PC), choisir high-speed steel (HSS) forets with a diameter 0.1-0.2mm smaller than the designed hole diameter (to compensate for material expansion during machining).
- For metal materials (alliage en aluminium, acier inoxydable), utiliser carbide drills—they have higher hardness and wear resistance. For stainless steel, it is recommended to choose drills with a special spiral angle (30°-40°) to improve chip removal efficiency.
3. Setup and Fixing: Ensure Stability to Reduce Errors
Unstable fixing of materials and incorrect tool installation will cause displacement during machining, resulting in deviations in hole positions. The following steps can ensure stable setup:
- Fixation des matériaux: Place the material on the CNC workbench and use fixtures (such as vises, pressure plates) to fix it. For thin materials (thickness less than 3mm), add a backing plate under the material to prevent the drill from piercing the workbench. After fixing, check the material with a dial indicator—ensure the runout is within 0.02mm.
- Tool Installation: Install the selected drill on the CNC spindle. Use a tool setting gauge to calibrate the tool length (to ensure accurate drilling depth) and tool radius. After installation, run the spindle at low speed (500r/min) pour 10 seconds to check if the tool runs smoothly without eccentricity.
4. Process Monitoring and Adjustment: Real-Time Optimization for Quality
During the processing of porous prototype models in CNC, real-time monitoring and parameter adjustment can timely solve problems and avoid batch defects.
Key Monitoring Points and Adjustment Methods
- Vitesse de broche: If the spindle speed is too high (Par exemple, 8000r/min for aluminum alloy), the tool will wear quickly; if it is too low (Par exemple, 2000r/min for aluminum alloy), the hole surface will be rough. The normal spindle speed range for aluminum alloy is 4000-6000r/min, and for stainless steel is 1500-3000r/min.
- Taux d'alimentation: For plastic materials, the feed rate can be set to 100-200mm/min; for metal materials, it is 50-150mm/min. If the feed rate is too fast, the drill may break; if it is too slow, the machining time will be prolonged.
- Chip Removal: Pendant l'usinage, observe the chip shape. For metal materials, continuous chips indicate normal processing; if the chips are broken into small pieces, it may be that the feed rate is too fast, and the feed rate needs to be reduced by 20%-30%.
5. Quality Control and Post-Processing: Improve Prototype Performance
Après traitement, strict quality control and appropriate post-processing can make the porous prototype meet the design requirements.
Quality Control Items
- Inspection visuelle: Check if there are burrs, fissure, or incomplete drilling around the holes.
- Inspection dimensionnelle: Use a caliper to measure the hole diameter (tolerance should be within ±0.05mm) and a coordinate measuring machine (Cmm) to detect the hole position accuracy (error should be less than 0.03mm).
Étapes de post-traitement
- Débarquant: Use a file or sandpaper (400#) to polish the burrs around the holes—this is especially important for threaded holes to avoid affecting the installation of screws.
- Nettoyage: Use alcohol or acetone to clean the prototype surface to remove cutting fluid and chips.
- Traitement de surface: Pour les prototypes métalliques, perform oxidation (alliage en aluminium) or passivation (acier inoxydable) treatment to improve corrosion resistance.
Yigu Technology’s Perspective on Processing Porous Prototype Models in CNC
À la technologie Yigu, we think processing porous prototype models in CNC requires the combination of design precision and practical experience. Many clients have problems like hole position deviation due to ignoring material fixing or tool calibration. We suggest using our self-developed CNC machining simulation software to test the program before formal processing, which can reduce 30% of trial machining errors. Entre-temps, our customized carbide tools for porous machining can improve tool life by 40% and machining efficiency by 25%, helping clients shorten the prototype development cycle.
FAQ
- Q: What should I do if the hole position is deviated when processing porous prototype models in CNC?
UN: D'abord, check if the material is fixed tightly—re-fix if it is loose. Alors, use a tool setting gauge to re-calibrate the tool length and radius. If the deviation still exists, check the CAM code for errors in hole coordinates and modify it if necessary.
- Q: Can I use the same tool to process holes of different diameters in a porous prototype?
UN: It is not recommended. Using a tool with a fixed diameter to process holes of different sizes will lead to unqualified hole diameters. You should prepare tools corresponding to each hole diameter to ensure the accuracy of each hole.
- Q: How to avoid tool breakage when processing deep holes (depth > 10mm) in porous prototypes?
UN: Adopt the “segmented drilling” method—drill 3-5mm each time, then lift the tool to remove chips. At the same time, increase the flow of cutting fluid to cool the tool and improve chip removal efficiency. Choose a drill with a longer flute to facilitate chip discharge.
