Vacuum Casting

Overview

Vacuum casting (also called urethane casting or silicone molding) is the ideal solution for producing 10-500 high-quality plastic parts without expensive injection molds. Using silicone molds created from 3D printed or CNC machined masters, we produce parts with properties nearly identical to injection molded components.

Perfect for bridge production, market testing, trade shows, and low-volume manufacturing. Choose from 100+ polyurethane materials that mimic ABS, PP, PC, PMMA, TPE, and other engineering plastics.

Vacuum Casting Capabilities

Parameter	Capability	Application
Quantity Range	10 – 500 parts	Small batch production
Mold Life	20 – 50 shots per mold	Multiple batches possible
Part Tolerance	±0.1mm – ±0.3mm	Functional parts
Max Part Size	1500 × 800 × 500mm	Large assemblies
Wall Thickness	0.8mm – 10mm	Thin to thick sections
Lead Time	5 – 10 days	Fast turnaround

🔧 Vacuum Casting Process

Step 1: Master Pattern Creation (2-3 Days)

A high-quality master pattern is created via SLA 3D printing or CNC machining. This master defines the final part geometry and surface finish. Surface quality is critical as it transfers to all cast parts.

Step 2: Silicone Mold Making (2-3 Days)

The master pattern is placed in a box and liquid silicone rubber is poured around it. After curing, the silicone mold is cut open and the master is removed. Multi-cavity molds can be created for higher volumes.

Step 3: Material Selection (Same Day)

Choose from 100+ polyurethane materials that mimic various thermoplastics. Materials range from rigid (ABS-like) to flexible (TPE-like), transparent (PMMA-like) to opaque, and standard to high-temperature grades.

Step 4: Vacuum Casting (1-2 Days)

Polyurethane resin is mixed, degassed under vacuum, and poured into the silicone mold. The mold is placed in a vacuum chamber to eliminate air bubbles, then cured in an oven at 60-80°C.

Step 5: Demolding & Post-Processing (1-2 Days)

Parts are removed from the silicone mold, gates are trimmed, and any necessary post-processing (sanding, painting, assembly) is completed.

Step 6: Quality Inspection & Shipping (1 Day)

Final parts are inspected for dimensional accuracy and cosmetic quality. Inspection report included. Parts shipped via express courier.

📦 Material Selection

Rigid Materials (ABS-like)

• PU 8400: General purpose, good balance of properties
• PU 8410: Higher impact strength, snap-fit applications
• PU 8420: Higher heat resistance (up to 80°C)

Flexible Materials (TPE/TPU-like)

• PU 9400: Shore A 80, general flexible applications
• PU 9410: Shore A 60, softer grip applications
• PU 9420: Shore A 90, higher wear resistance

Transparent Materials (PMMA/PC-like)

• PU 5400: Crystal clear, optical applications
• PU 5410: UV resistant, outdoor applications

High-Temperature Materials

• PU 8800: Heat resistant up to 120°C
• PU 8810: Glass-filled, higher stiffness

🎯 Applications

Application	Typical Quantity	Benefits
Bridge Production	50-200 parts	Sell while waiting for molds
Market Testing	20-100 parts	Validate demand risk-free
Trade Shows	10-50 parts	Production-quality display units
Beta Testing	30-100 parts	Functional parts for customers
Low-Volume Production	100-500 parts	Cost-effective for small batches

🔍 Quality Control

• First Article Inspection: Complete dimensional report on first parts
• Visual Inspection: Check for bubbles, inclusions, surface defects
• Hardness Testing: Shore A/D verification for flexible/rigid materials
• Color Matching: Spectrophotometer verification for color-critical parts
• Functional Testing: Assembly fit, performance testing as required

💰 Cost Comparison

Method	Tooling Cost	Part Cost	Best Quantity
Vacuum Casting	$ (Low)	$$	10-500 parts
Rapid Tooling	$$ (Medium)	$$	500-5K parts
Injection Molding	$$$ (High)	$	5K+ parts