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Vacuum Casting

Vacuum casting (also called polyurethane casting or silicone molding) is a versatile manufacturing process for producing high-quality prototypes and low-volume end-use parts. Combining the flexibility of silicone molds with the precision of vacuum-assisted resin casting, this method bridges the gap between 3D printing and mass production. Ideal for functional testing, design validation, and small-batch production, vacuum casting delivers near-injection-molding quality at a fraction of the cost and time.

Key Features & Benefits

1. Precision & Surface Quality
Vacuum casting achieves:
Dimensional accuracy: ±0.15% per 100mm (typical ±0.2mm for small parts)
Surface finish: Ra 0.8–1.6μm (comparable to injection molding)
Fine details: Reproduces textures, logos, and thin walls (down to 0.5mm)
Low porosity: Vacuum degassing eliminates bubbles in resin

2. Material Options
Engineered polyurethanes mimic production-grade plastics:
ABS-like: Tough, impact-resistant
PP-like: Flexible, fatigue-resistant
PC-like: High strength, transparent options
High-temp resins: Up to 180°C
Rubber-like: Shore A 30–90 hardness

3. Fast Turnaround
Prototypes: 3–5 days (from approved master model)
Low-volume production: 10–15 days for 20–50 parts
No tooling delays: Silicone molds cure in 6–8 hours vs. weeks for steel molds

4. Cost Efficiency
Mold costs 90% less than injection molding
Ideal for 10–500 pieces (breakeven vs. 3D printing at ~20 units)
No minimum order quantity

Process Steps

1. Master Pattern Creation
A 3D-printed, CNC-machined, or hand-finished master model is prepared (surface polished to desired finish).

2. Silicone Mold Making
The master is placed in a casting box, and liquid silicone is poured around it.
Vacuum degassing removes air bubbles for defect-free molds.
Cured at 40°C for 6–8 hours; molds last 15–25 cycles.

3. Resin Casting
Polyurethane resin is mixed, degassed, and injected into the mold under vacuum.
Curing takes 1–2 hours (faster with heated chambers).

4. Post-Processing
Parts are demolded, trimmed, and finished (painting, plating, or assembly).
Applications
Functional prototypes: Test fit, form, and function
Pre-production samples: Market validation before mass production
Low-volume end-use parts: Medical devices, automotive components, consumer electronics
Soft-touch overmolds: Grips, buttons, seals

Comparison to Other Processes

	Factor Vacuum Casting	Injection Molding	3D Printing
Lead Time	3–15 days	4–8 weeks	1–5 days
Cost (1–100pcs)	$$$	$$$$$ (tooling)	$$
Torelence	±0.1mm	±0.001mm	±0.25mm (FDM)
Surface Finish Smooth, mold-like Very smooth Layer lines (unless post-processed)
Best For 10–500 pieces 1,000+ pieces 1–10 pieces

Why Choose Vacuum Casting?

Faster than injection molding – No steel tooling required
Better quality than 3D printing – No layer lines, wider material selection
Cost-effective for small batches – Avoid high upfront tooling costs
Need functional prototypes or low-volume parts?
Upload your CAD file for a free DFM review and quote within 24 hours!

Sharing Of Finished Mold Products

If you would like to learn more about these finished products, you can click to find out more details about them.

Replica Mold Tooling

Case 1 is our case in 2019,
It is a front bumper of a car,
It took 9 days,
Size: 1800*600*18 (thickness) mm
Tolerance controlled at ±0.3MM.

Transparent Replica Mold Tooling

Case 2 is our product in 2020.
Applied to the shell of a certain device.
It took 4 days,
Size: 200*50*30mm
Tolerance controlled at ±0.1MM

Introduction to the Advantages of Processing Services

Vacuum Casting is a highly efficient manufacturing process that bridges the gap between prototyping and mass production. Combining the flexibility of silicone molds with the precision of vacuum-assisted resin casting, this method is ideal for producing high-quality, functional prototypes and low-volume end-use parts. Below are the key advantages of vacuum casting, focusing on precision, lead time, and overall cost-effectiveness.

1. Exceptional Precision & Surface Quality
Vacuum casting delivers near-injection-molding accuracy, making it perfect for complex geometries and fine details:
Dimensional tolerance: ±0.15% per 100mm (typically ±0.2mm for small parts)
Surface finish: Smooth, mold-like texture (Ra 0.8–1.6μm) without layer lines
Fine feature reproduction: Captures textures, logos, and thin walls (down to 0.5mm)
Low porosity: Vacuum degassing eliminates air bubbles, ensuring structural integrity
Compared to 3D printing, vacuum casting provides better surface quality and more consistent mechanical properties, while matching injection-molding precision at a fraction of the cost.

2. Rapid Turnaround – From Days to Weeks
One of the biggest advantages of vacuum casting is its fast production speed:
Prototypes in 3–5 days (after master model approval)
Low-volume batches (10–50 parts) in 10–15 days
No metal tooling required – Silicone molds cure in 6–8 hours (vs. weeks for steel molds in injection molding)
This makes vacuum casting ideal for:
Functional testing (fit, form, and performance validation)
Market-ready prototypes (for investor demos or user testing)
Pre-production runs (before committing to expensive tooling)

3. Material Versatility – Mimicking Production-Grade PlasticsVacuum casting uses polyurethane resins that closely replicate engineering-grade thermoplastics, including:
ABS-like (tough, impact-resistant)
PP-like (flexible, fatigue-resistant)
PC-like (high strength, transparent options)
Rubber-like (Shore A 30–90 hardness for soft-touch parts)
High-temp resins (up to 180°C for thermal testing)
This allows engineers to test materials that behave like final production parts without investing in expensive molds.

4. Cost-Effective for Low-Volume Production
Vacuum casting is significantly cheaper than injection molding for small batches:
Mold costs 90% less than steel tooling
Ideal for 10–500 pieces (breakeven vs. 3D printing at ~20 units)
No minimum order quantity – Produce as few as 1–2 parts
This makes it perfect for:
Startups (low-budget prototyping)
Medical & automotive (customized small-batch components)
Consumer electronics (housing prototypes with fine details)

5. Superior to 3D Printing & Injection Molding for Mid-Range Requirements

Factor	Vacuum Casting	3D Printing	Injection Molding
Lead Time	3–15 days	1–5 days	4–8 weeks
Cost (1–100pcs)	$$$	$$	$$$$$
Tolerances	±0.2mm	±0.1mm	(FDM) ±0.1mm
Surface Finish	Smooth, mold-like Layer lines (unless post-processed) Very smooth

Conclusion: When to Choose Vacuum Casting?
Need high-quality prototypes that look & function like final products?
Require fast turnaround (days, not weeks)?
Producing low volumes (10–500 units) without expensive tooling?

Vacuum casting is the perfect balance between speed, precision, and affordability.

Ready to test your design? Upload your CAD file for a free DFM review and quote within 24 hours!

Vacuum Casting: Design to Premium Parts

Vacuum casting is a versatile manufacturing method ideal for producing functional prototypes and low-volume end-use parts with injection-molding-like quality. Below is a step-by-step breakdown of the process, including precision capabilities and lead times at each stage.

Step 1:

Master Model Preparation (1–3 Days)

The process begins with creating a high-quality master pattern:
3D Printing (SLA/DLP): Produces models with ±0.1mm accuracy and smooth surfaces.
CNC Machining: For metal or high-temp master patterns (±0.05mm tolerance).
Hand Finishing: Polishing to achieve Ra <0.6μm surface quality.
Lead Time: 1–3 days (depending on complexity).
Step 2:

Silicone Mold Making (6–8 Hours per Mold)

The master is encased in liquid silicone to create a flexible mold:
Vacuum Degassing: Removes air bubbles for defect-free molds.
Curing: Heated at 40–50°C for 6–8 hours.
Mold Life: Typically 15–25 cycles before degradation.
Precision: Molds replicate details down to 0.2mm with ±0.15% dimensional accuracy.
Step 3:

Resin Casting (1–2 Hours per Batch)

Polyurethane resin is poured into the mold under vacuum:
Material Options: ABS-like, PP-like, PC-like, rubber-like (Shore A 30–90).
Vacuum Assistance: Ensures zero porosity and full cavity filling.
Curing: Parts solidify in 1–2 hours (faster with heated chambers).
Tolerance: Final parts maintain ±0.2mm accuracy for small components.
Step 4:

Demolding & Post-Processing (1 Day)

Careful Extraction: Prevents damage to delicate features.
Trimming: Removal of sprues and flash.
Surface Finishing: Painting, plating, or texture application.
Lead Time: Post-processing adds <1 day for most projects.

What Our Customers Say

Andrew

The precision and quality of your machined parts are outstanding! They fit perfectly into our assembly with zero issues. Will definitely order again!

2024.10.3

Peter

Excellent work! The parts were delivered on time and met all our specifications. Your attention to detail is impressive. Highly recommended!

2024.10.3

Gowthaman

We're very satisfied with the machining services provided. The finish and tolerances are exactly as required. Great job and smooth communication throughout!

2024.10.3

Romen

Consistently high-quality machining services. This is our third order, and as always, no complaints. Keep up the great work!

2024.10.3

Let Us Turn Your Ideas Into Reality - Send Your Inquiry Now!

Seem you may requirements functional prototypes or low-volume production parts that look and perform like the real thing—without the cost or wait of injection molding? Our vacuum casting service delivers injection-molding-quality parts in just days, not weeks!
Why Choose Us for Vacuum Casting? Speed to Market – Get first samples in 3–5 days (perfect for tight deadlines!)
Production-Grade Materials – ABS-like, PP-like, rubber-like, and high-temp resins
Precision & Detail – ±0.2mm tolerances, smooth finishes (Ra 0.8–1.6μm)
Cost-Effective – No steel tooling needed—ideal for 10–500 pieces
End-to-End Support – From design optimization to painting, plating, and assembly
How It Works:
1. Share Your CAD File (or let us help refine it)
2. We Create a Silicone Mold (lasts 15–25 cycles)
3. Cast in Your Chosen Material (20+ resin options)
4. Deliver Ready-to-Use Parts (with optional post-processing)

Vacuum Casting

Key Features & Benefits

Process Steps

Comparison to Other Processes

Why Choose Vacuum Casting?

Sharing Of Finished Mold Products

Replica Mold Tooling

Transparent Replica Mold Tooling

Introduction to the Advantages of Processing Services

Vacuum Casting: Design to Premium Parts

What Our Customers Say

Andrew

Peter

Gowthaman

Romen

Let Us Turn Your Ideas Into Reality - Send Your Inquiry Now!

Quick Links

Product Category

Contact Us

Vacuum Casting

Key Features & Benefits

Process Steps

Comparison to Other Processes

Why Choose Vacuum Casting?

Sharing Of Finished Mold Products

Replica Mold Tooling

Transparent Replica Mold Tooling

Introduction to the Advantages of Processing Services

Vacuum Casting: Design to Premium Parts

What Our Customers Say​​​​​​​

Andrew

Peter

Gowthaman

Romen

Let Us Turn Your Ideas Into Reality - Send Your Inquiry Now!

Quick Links

Product Category

Contact Us

What Our Customers Say