Rapid Tooling (RT)

A broad set of techniques that use additive manufacturing or other fast processes to create molds, dies, or patterns quickly and cost-effectively for prototyping and low-volume production.

Bridge Tooling

Tooling that serves as a "bridge" between prototyping and full-scale production. It is more robust than a simple prototype mold but not as durable as production tooling.

Soft Tooling

A general term for molds made from less durable materials, typically used for 50-1,000 parts. Common materials include aluminum, soft steel, silicone rubber, and epoxy composites.

Hard Tooling

Refers to traditional, long-life production molds made from hardened steel. These are designed for high-volume production (millions of cycles) and involve high cost and long lead times.

Indirect Rapid Tooling

A method where a master pattern (usually 3D printed) is first created. This pattern is then used to produce a secondary, negative mold (e.g., from silicone or epoxy), which is used to cast the final parts.

Direct Rapid Tooling

A method where the tool itself (e.g., a mold insert) is fabricated directly using an additive process, such as Direct Metal Laser Sintering (DMLS).

Mold Life / Number of Shots

The estimated number of parts that can be produced from a mold before it fails or its accuracy degrades. This is the key trade-off in RT (e.g., a silicone mold may have a life of 25 shots, while a soft aluminum mold may last for 10,000).

Master Pattern

A high-fidelity, dimensionally accurate model of the final part, used in indirect methods to create the mold. It is typically produced using Stereolithography (SLA) or Material Jetting for high surface quality.

Silicone Rubber Molding

Another name for the Vacuum Casting process. The mold is made from Room Temperature Vulcanizing (RTV) silicone rubber.

Vacuum Casting

A primary indirect RT process. A vacuum is used to draw liquid polyurethane resin into a silicone mold, ensuring the resin fills intricate details and minimizing air bubbles.

RTV Silicone

Room Temperature Vulcanizing Silicone. The two-part silicone rubber used to make flexible molds; it cures at moderate temperatures.

K-Factor (Shrinkage Factor)

A multiplier applied to the CAD model of the master pattern to compensate for the cumulative shrinkage of both the mold material (silicone) and the cast material (polyurethane).

Direct Metal Laser Sintering (DMLS)

An additive manufacturing process that uses a laser to sinter/fuse fine metal powder particles layer by layer to build a fully dense metal part. Used to create metal mold inserts directly from CAD data.

Selective Laser Melting (SLM)

Similar to DMLS, but the metal powder is fully melted rather than sintered, resulting in parts with different mechanical properties.

Binder Jetting

An additive process where a liquid binding agent is selectively deposited to join powder particles (polymer, sand, or metal). In RT, it's famously used for 3D printed sand molds for metal casting.

RapidSteel / LaserForm

Historic tradenames for metal-polymer composites or metal powders used in early direct metal RT processes. The terms are sometimes still used generically.

Epoxy Composite Tooling

A method where a mold is made from an epoxy resin filled with conductive materials like aluminum or copper powder to improve strength and thermal performance.

Sprayed Metal Tooling

A process where a thin shell of metal (e.g., zinc or aluminum) is thermally sprayed onto a master pattern. The shell is then backed with a strong filler like epoxy or ceramic to create a mold.

Soft Aluminum Mold

A mold machined from a block of aluminum (e.g., 6061 or 7075). It is "soft" because it is not heat-treated. It offers a good balance of speed, cost, and life for Bridge Tooling.

Kirksite

A low-melting-point zinc alloy that can be cast into a mold shape. It is easy to machine and repair but has a relatively low melting point, limiting its use to lower-temperature processes.

Mold Insert

A block, often containing the core or cavity of the mold, that is inserted into a standard mold base. RT is often used to create these inserts.

Mold Base

A standardized frame that holds the mold inserts, ejection system, and cooling channels. Using a standard base saves cost and time.

Conformal Cooling Channels

A major advantage of Direct Metal RT. Cooling channels are 3D printed to conform to (follow) the shape of the part cavity, leading to faster, more uniform cooling than straight drilled channels.

Draft Angle

A slight taper applied to vertical faces of a part to facilitate its ejection from the mold. Critical for all molding processes.

Parting Line

The line or plane where the two halves of a mold meet.

Shrinkage Allowance

The dimensional compensation factored into the tool's design to account for the material shrinkage of the final part material (e.g., polypropylene shrinks significantly) as it cools.

Functional Prototype

A prototype made via RT that is used to verify not just shape, but also fit, function, and performance under conditions that simulate the final product.

Low-Volume Production

The manufacture of end-use parts in quantities from 10s to 1,000s, for which traditional hard tooling is not economical. This is the primary application of RT.

Pilot Run

A small-scale production run used to validate the manufacturing process, train assembly staff, and produce parts for market testing before full-scale production begins.

Technology Readiness Level (TRL)

A scale used to estimate the maturity of a technology. RT helps raise the TRL by enabling the creation of parts from the intended manufacturing process.

Lifecycle (of a Tool)

The stages a tool goes through, from design and fabrication to production use and eventual decommissioning. RT tools have a shorter but much faster lifecycle.