Rapid Prototyping for Metal and Plastic Parts Processing
In the development of metal and plastic products, rapid prototyping serves as a bridge between design and mass production. By quickly creating physical prototypes, companies can:
Verify design feasibility: Test structure, assembly, and functionality early.
Shorten development cycles: Reduce from weeks to days, accelerating time-to-market.
Lower development costs: Minimize mold modification risks and avoid rework during production.
Improve client communication: Provide tangible samples for confirmation, reducing misunderstandings.
Technologies & Processes
A. For Metal Parts:
CNC Machining: Ideal for aluminum, steel, brass. Offers high precision, real material properties. Best for functional, load-bearing, high-tolerance parts.
Laser Cutting & Bending: For sheet metal prototypes (enclosures, brackets). Fast and cost-effective.
Metal 3D Printing (SLM/DMLS): For complex, lightweight designs (lattice structures, internal channels) in stainless steel, titanium, or aluminum.
B. For Plastic Parts:
CNC Machining (Plastics): Uses ABS, PC, Nylon, POM. Provides true material performance for stress testing.
3D Printing:
SLA/DLP: High surface finish, fine details. Perfect for appearance models, clear parts.
SLS: Nylon-based, no supports needed. Great for snap-fits, hinges, functional assemblies.
FDM: Lowest cost, fast. Suitable for conceptual models, large simple parts.
Vacuum Casting (Urethane Casting): Uses silicone molds to produce 10-100 parts in various colors/material properties. Ideal for pre-production runs, user testing.
Application-Based Selection Guide
Match the technology to the need:
"I just need to see and feel the shape" → SLA 3D Printing or CNC + Painting.
"I need to test gear strength and wear" → POM CNC or Nylon SLS.
"I must verify metal-to-plastic assembly" → Aluminum/Steel CNC + Plastic CNC or SLS.
"I need 50 units for a trade show" → Vacuum Casting.
"My design has impossible internal metal geometry" → Metal 3D Printing.
Standard Workflow
1. Requirement Analysis: Define purpose, material, quantity, budget, timeline.
2. Design for Manufacturability (DFM) Review: Optimize design for prototyping and future production.
3. Process Selection & Quotation: Recommend the best technical solution.
4. Data Preparation: Submit 3D files (STEP/IGS), finalize details.
5. Production & Post-Processing: Machining/printing, plus finishing (sanding, painting, anodizing, plating).
6. QC & Delivery: Provide inspection report (critical dimensions) and physical samples.
Metal Rapid Prototyping Technologies
CNC Machining (Metal)
Suitable Materials: Aluminum alloys, Stainless steel, Copper, Titanium alloys, Tool steel
Technical Features:
Accuracy up to ±0.025-0.1mm
Material properties identical to final product
Excellent surface quality, suitable for various surface treatments
Typical Applications:
Mechanical structural parts, connectors
Housings, brackets, bases
Precision transmission components
Advantages: High precision, real materials, high strength
Limitations: Limited ability for complex internal structures, significant material waste
Sheet Metal Laser Prototyping
Process Combination: Laser cutting + CNC bending + Welding
Technical Features:
Rapid prototyping of thin-walled metal structures
High cost-effectiveness
Capable of producing large sheet metal parts
Typical Applications: Enclosures, cabinets, housings, brackets, protective covers
Metal 3D Printing
Main Technologies: SLM (Selective Laser Melting), DMLS (Direct Metal Laser Sintering)
Materials: Stainless steel, Aluminum alloys, Titanium alloys, Tool steel, Cobalt-chrome alloys
Unique Advantages:
Manufacture complex geometries impossible with traditional methods
Integrated forming, reducing assembly needs
Enable lightweight designs
Application Scenarios: Complex cooling channels, lightweight structures, customized implants, mold inserts
Get A QoutePlastic Rapid Prototyping Technologies
CNC Plastic Machining
Suitable Materials: ABS, PC, PMMA, Nylon, POM, PEEK
Advantages:
Uses real engineering plastics, reliable performance
High precision, suitable for precision fitting parts
Good surface finish
Applications: Gears, bearings, housings, transparent windows, high-load test parts
Vacuum Casting (Silicone Molding)
Process: Create master pattern → Make silicone mold → Cast polyurethane resin
Material Options: ABS-like, PP-like, PC-like, transparent, flexible resins
Core Value:
Rapid small-batch production (10-500 pieces)
Multiple material hardness options
Cost significantly lower than steel mold tooling
Typical Applications: Market testing, crowdfunding samples, exhibition prototypes, small batch sales
3D Printing Technologies
SLA/DLP
Material Options:Various photosensitive resins; Accuracy: High (±0.1mm); Strength: Medium ; Surface Quality: Excellent, comparable to injection molding
SLS
Material Options:Nylon (PA), Glass-filled nylon; Accuracy:Medium (±0.15mm); Strength: High, close to injection molding ; Surface Quality: Slightly rough, can be post-processed
FDM
Material Options:Various photosensitive resins; Accuracy: Lower (±0.2mm); Strength: Medium ; Surface Quality: Visible layer lines
PolyJet
Material Options:ABS-like resins, Flexible materials; Accuracy: Very high (±0.1mm); Strength: Medium ; Surface Quality: Excellent, smooth and detailed
Rapid Prototyping Process Selection Decision Guide
I. Core Decision Dimensions
When quickly selecting a process, focus on these 5 key dimensions:
Accuracy Requirement (Within ±0.1mm?)
Material Authenticity (Need real engineering materials?)
Lead Time (How fast do you need it?)
Budget Constraint (How much can you spend?)
Prototype Purpose (Appearance showcase / Functional testing / Small batch?)
II. Quick Selection Guide
Ask yourself these three key questions:
Question 1: What is it for?
Just to see the look → Choose SLA (best surface finish)
To test function/strength → Choose CNC Machining or SLS Nylon Printing (realistic materials)
Need 10-100 samples → Choose Vacuum Casting (lowest cost per part)
Extremely complex geometry → Choose 3D Printing (SLA/SLS)
Question 2: Does the material matter?
Must use real metal/plastic → Must choose CNC Machining
Simulation is acceptable → Can choose 3D Printing or Vacuum Casting
Question 3: What’s the timeline and budget?
Need it tomorrow, low budget → FDM or SLA 3D Printing
Within 3 days, medium budget → CNC Machining
~1 week, need multiple copies → Vacuum Casting
Get A QouteTechnical and Economic Analysis
1.1 Cost Structure Comparison
3D Printing: Main cost = Material + Machine time, suitable for complex geometries
CNC Machining: Main cost = Programming + Machining time + Material waste, suitable for high-precision simple geometries
Vacuum Casting: Main cost = Mold cost + Per-part material cost, suitable for small batches (10+ pieces)
1.2 Time Efficiency Analysis
Fastest: Simple 3D printing (several hours)
Most Common: CNC (1-3 days)
Small Batches: Vacuum casting (3-7 days)
Successful Application Cases
Case 1: Smart Lock Development
Challenge: Verify assembly between metal lock body and plastic housing, and electronic component layout
Solution:
Lock body: Aluminum CNC machining + Anodizing
Housing: SLA printing + Painting
Internal brackets: Sheet metal laser forming
Result: Identified 3 assembly interferences in advance, saved ¥150,000 in mold modification costs
Case 2: Medical Handheld Device
Challenge: Ergonomic testing and sterilization validation
Solution:
Main body: SLS nylon printing (heat-resistant for sterilization)
Buttons: SLA transparent resin (verify internal lighting effects)
Seals: Silicone casting
Result: Optimized grip angle, passed actual sterilization testing
Case 3: Industrial Robot End Effector
Challenge: Balance lightweight design with high strength
Solution:
Main structure: Titanium metal 3D printing (topology optimized design)
Connectors: Stainless steel CNC machining
Get A Qoute
Best Practices and Recommendations
1.1 Design Optimization Suggestions
Design for Rapid Prototyping:
CNC: Consider tool accessibility, avoid deep and narrow cavities
3D Printing: Optimize support structures, consider print orientation effect on strength
Vacuum Casting: Include draft angles, reserve gate locations
File Preparation Standards:
Provide 3D files in STEP or IGES format
Indicate critical dimensions and tolerance requirements
Specify surface treatment needs clearly
1.2 Supplier Selection Criteria
Technical Capability: Possession of multiple process technologies
Quality System: Established inspection procedures
Design Support: Ability to provide professional DFM advice
NDA/Confidentiality: Emphasis on intellectual property protection
1.3 Development Trends
Hybrid Manufacturing: Combined 3D printing and CNC processing
New Material Development: Higher-performance rapid prototyping materials
Digital Services: Online quoting, real-time production tracking
Automated Post-processing: Robotic polishing, automated painting
Conclusion
Rapid prototyping technologies for metal and plastic provide unprecedented flexibility in product development.
Correct selection and application of these technologies can:
Shorten product development time by 50-70%
Reduce development costs by 30-50%
Significantly increase first-time mold success rate
Accelerate innovation cycles, enhance market competitiveness
Get an online quote and injection molding design analysis today.