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Small Batch / Customized Production

Soft Tooling (Vacuum Casting)

Vacuum casting is a specialized technique that uses precise silicone molds made from a 3D-printed or CNC-machined master model, often referred to as silicone molding or soft tooling. This method involves casting polyurethane (PU) parts under vacuum conditions, ensuring bubble-free production and accurate reproduction of fine details with minimal tolerance deviations. Compared to CNC machining, vacuum casting is faster and more cost-effective for producing multiple identical parts.

Our silicone molding services can be customized to meet client needs, including specific color requirements during the molding process. We can also integrate other components into the mold (e.g., rubber over plastic or soft material over hard material) to enhance the product’s quality and feel.

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Advantages of the Process

High Precision

Achieves fine surface detail, replicating the aesthetic quality of injection-molded parts.

Cost Efficiency

Minimizes the time and cost of traditional manufacturing processes, accelerating the product development cycle, making it ideal for small-batch production. (Each mold can produce up to 15-25 pcs)

Versatility

Supports a wide range of materials, colors, and surface finishes, catering to customer customization needs.

Soft Tooling Mold

Assembled Prototype

Silicone Mold

Overmolding product

Vacuum Casting Machine

	Soft Tooling (vacuum casting)	Reaction Injection Molding (Low pressure injection)	Rapid Tooling / Injection Molding (aluminum mold or soft steel mold + mass production injection)
Mold material	RTV Silicone (Soft Mold)	Silicone, FRP/GRP, Aluminum Powder Epoxy Resin	Aluminum alloy/mild steel P20, S50C, NAK80, etc.
Mold cost (relative)	$	$$	Aluminum Mould $$$ / Steel Mould $$$$$
Mold delivery time (general situation)	3 – 7 working days	5 – 15 working days	15 – 35 working days
Single mode life	15 – 25 pieces	50 (Silicone) – 3,000 pcs (Aluminum Powder Epoxy Resin)	Aluminum moulds 10,000 – 20,000 pieces Steel moulds 100,000 – 500,000 pieces
Cavity pressure/ Clamping force	Vacuum → 0.05 MPa / Almost no clamping	0.3 – 1 MPa / 5 – 30 ton	70 – 200 MPa / 75 – 800 tons
Common materials for finished products	* PU (ABS‑like, PC‑like, transparent PMMA‑like) * High heat resistant PU (120 °C) * Elastomer PU / Silicone (Shore A 30‑90) * Conductive, flame retardant, filling grade special resin	* Solid or micro-foamed PU / PUA * Glass fiber reinforced PU (RRIM / SRIM) * DCPD, Nylon-RIM (Caprolactam) * Reactive EP, Polyester	* ABS, PC, PC/ABS, PP, PE, POM, PBT * PA6 / PA66 (including GF, CF) * PMMA, ASA, TPU/TPE and other thermoplastics
Cycle time/piece	30 – 60 min	2 – 5 min	20 – 60 s
Recommended ordering batch	8 items↑	50 items↑	5,000 pieces↑ (MOQ 5,000 pcs)
Common size range	≤ 0.5 m	≤ 2 m Large enclosures possible	≤ 1 m; potentially limited by the clamping force of the injection molding machine
Possible wall thickness	1 – 6 mm; uniform thickness is the most stable	2 – 20 mm, thick and thin can be mixed	0.8 – 4 mm; thickness difference requires flow channel balance
Dimensional accuracy	±0.20 mm /100 mm	±0.15 mm /100 mm	±0.05 mm /100 mm
Surface quality	0.1 mm texture can be copied; spray painting is required	Available in Class-A paint or leather texture	The mold surface can directly achieve mass production texture or high gloss
Typical advantages	Low mold opening fee, fast delivery, high flexibility	Low mold cost, large size, mixed thickness, impact resistance	Lowest unit cost, best precision, most materials and colors
Common Applications	Appearance/functional prototypes, samples, small batch internal components	Automobile bumpers, medical/industrial large panels, structural foam parts	Mass production of consumer goods, precision gears, fasteners, and large-volume structural parts

Scope of Services

Mockup Sample Prototyping

We create realistic product models or prototypes based on customer-provided requirements and drawings. These models accurately replicate the intended design, allowing for detailed evaluation and testing before moving to mass production.

Mass Production

We can achieve small-scale batch production of identical parts, with the master mold having a lifespan of producing 15 to 25 pieces.

On-demand Manufacturing

We provide just-in-time production based on customer needs, minimizing storage and inventory costs. This approach ensures efficient production while reducing overhead related to warehousing and excess stock.

Blog and Knowledge Base

Blog

The Science of the Soft Mold: A Deep Dive into Why Vacuum Casting Tolerances Differ from CNC Machining

Blog

Beyond the Sweet Spot: The Four Critical Boundaries of Vacuum Casting for Low-Volume Production

Knowledge Base

Our Knowledge Base

Please refer here for more basic knowledge / detail / FAQ about this technique. →

Basic Processing Materials

Plastics

Rubber

Rubber is valued for its flexibility and shock-absorbing properties, making it ideal for products like seals or gaskets that need to withstand continuous bending and pressure. We can also adjust the hardness of the rubber to meet specific requirements.

ABS

ABS is strong, durable, and offers good heat resistance and impact resistance, making it a preferred plastic for general parts and consumer products.

PC

PC (Polycarbonate) is highly durable, offering excellent impact resistance and good transparency.

PP

PP (Polypropylene) is tough and offers excellent chemical resistance, making it commonly used in parts and packaging that come into contact with chemical solvents.

CMF Options

Material Properties

We provide a wide range of materials, including metals, plastics, and composites.

Surface Finishings

We offer superior surface finishes that enhance part durability and aesthetics for applications requiring smooth or textured surfaces.

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Applied Industries

IDMockup offers top-notch manufacturing capabilities, whether for rapid prototyping or custom production orders. Our self-owned factories and satellite factories are equipped to efficiently produce complex, high-quality parts.