Rapid prototyping in 3D printing represents a transformative approach to product development, enabling designers and engineers to quickly convert digital concepts into physical models. This technology has evolved from purely conceptual visualization tools to sophisticated manufacturing processes capable of producing functional prototypes and even end-use parts. The integration of computer-aided design with additive manufacturing technologies has revolutionized how products are developed, tested, and brought to market across industries ranging from medical devices to aerospace components and consumer products.
Rapid prototyping is a group of techniques used to quickly fabricate a scale model of a physical part or assembly using three-dimensional computer aided design (CAD) data. Construction of the part or assembly is usually done using 3D printing technology. The term itself has evolved significantly since its introduction in the mid-1980s.
In the 1980s, 3D printing techniques were considered suitable only for the production of functional or aesthetic prototypes, and the more appropriate term at that time was “rapid prototyping.” By 2019, the precision, repeatability, and material range of 3D printing had increased to the point that some 3D printing processes are now considered viable as industrial-production technologies. In this context, the term “additive manufacturing” can be used synonymously with “3D printing”.
The first methods for rapid prototyping became available in mid-1987 and were used to produce models and prototype parts. Today, they are used for a wide range of applications and can be used to manufacture production-quality parts in relatively small numbers without the typical unfavorable short-run economics that characterized traditional manufacturing methods.
The historical trajectory of rapid prototyping technology includes several key milestones:
1984: Chuck Hull filed a patent for stereolithography fabrication (SLA), defining the process as a “system for generating three-dimensional objects by creating a cross-sectional pattern of the object to be formed.” Hull’s contribution included the STL file format and the digital slicing and infill strategies common to many processes today.
1988: Scott Crump developed fused deposition modeling (FDM), a special application of plastic extrusion, which was later commercialized by his company Stratasys. This technology is now used by most consumer-oriented 3D printers.
1993: MIT developed a powder bed process employing standard and custom inkjet print heads, which was originally what the term “3D printing” referred to specifically. The same year saw the start of Solidscape, introducing a high-precision polymer jet fabrication system with soluble support structures.
1995: The Fraunhofer Institute developed the selective laser melting process, expanding the capabilities of additive manufacturing to include metal parts.
2009: FDM printing process patents expired, leading to a proliferation of consumer-grade 3D printers and widespread adoption of the technology.
As these additive processes matured, it became clear that metal removal would no longer be the only metalworking process, as tools or heads moving through a 3D work envelope could transform raw materials into desired shapes layer by layer, opening new possibilities for manufacturing.
The typical workflow in rapid prototyping begins with creating geometric data, either as a 3D solid using a CAD workstation or as 2D slices using a scanning device. For rapid prototyping, this data must represent a valid geometric model—one whose boundary surfaces enclose a finite volume, contain no holes exposing the interior, and do not fold back on themselves.
The model is valid if, for each point in 3D space, the computer can determine uniquely whether that point lies inside, on, or outside the boundary surface of the model. CAD post-processors approximate the application vendors’ internal CAD geometric forms with simplified mathematical expressions, which are then converted to the STL file format—a de facto standard for transferring solid geometric models to additive manufacturing machines.
To drive the actual manufacturing mechanism, the prepared geometric model is typically sliced into layers, and these slices are scanned into lines, producing a “2D drawing” used to generate trajectories similar to CNC toolpaths. This process mimics, in reverse, the layer-by-layer physical building process that will occur during printing.
ISO/ASTM52900-15 defines seven categories of Additive Manufacturing (AM) processes:
Vat Photopolymerization: Uses liquid photopolymers that cure under light exposure, creating highly detailed parts. Stereolithography (SLA) falls into this category.
Material Jetting: Similar to traditional 2D printing but deposits materials layer by layer to build 3D objects. This technique allows for multi-material and multi-color printing.
Binder Jetting: Deposits a binding agent onto layers of powder material. This technique can work with ceramics, metals, and polymers.
Powder Bed Fusion: Includes Selective Laser Sintering (SLS) and Direct Metal Laser Sintering (DMLS). These processes use lasers to selectively fuse powder materials, creating strong, complex parts.
Material Extrusion: Includes the most widely used technique, Fused Deposition Modeling (FDM). This process extrudes thermoplastic filaments layer by layer through a heated nozzle.
Directed Energy Deposition: Typically used for metal repairs or adding material to existing parts, using focused thermal energy to fuse materials as they are deposited.
Sheet Lamination: Bonds and cuts sheets of material to form objects, using paper, plastic, or metal sheets.
Each technology has distinct advantages and limitations regarding speed, precision, material compatibility, and cost effectiveness, making certain processes more suitable for specific applications or industries.
Traditionally, 3D printing focused primarily on polymers due to the ease of manufacturing and handling polymeric materials. However, the field has rapidly evolved to include not only a wide variety of polymers but also metals and ceramics, making 3D printing an increasingly versatile option for manufacturing.
For common 3D printing technologies, various polymer materials are available:
Photopolymer Resins (SLA): Starting from $0.4 per gram, these UV-curable resins offer excellent detail and surface finish, suitable for visual prototypes, jewelry molds, and dental applications.
Nylon Powders (SLS): Starting from $0.7 per gram, these provide good mechanical properties, heat resistance, and chemical stability, making them ideal for functional prototypes, end-use parts, and complex assemblies.
Thermoplastic Filaments (FDM): Including PLA, ABS, PETG, TPU, and specialty filaments. These vary widely in price and properties, offering options for everything from basic conceptual models to functional, heat-resistant parts.
Metal 3D printing has revolutionized prototyping for industries requiring durable, high-performance parts:
Aluminum Alloys: Lightweight with good mechanical properties, used in aerospace, automotive, and consumer electronics prototypes.
Stainless Steel: Offers excellent corrosion resistance and strength, ideal for medical devices, kitchen appliances, and industrial equipment prototypes.
Titanium Alloys: Providing exceptional strength-to-weight ratio and biocompatibility, perfect for aerospace components, medical implants, and high-performance automotive parts.
Direct metal printing technologies tend to be expensive, with costs for printers and materials significantly higher than polymer-based systems. However, alternative approaches include using less expensive printers to create molds for casting metal parts.
When selecting materials for rapid prototyping, several factors should be considered:
Intended Use: Whether the prototype is for concept visualization, functional testing, or end-use application.
Required Properties: Mechanical strength, flexibility, heat resistance, chemical resistance, etc.
Detail and Surface Finish: The level of detail and surface quality required.
Post-Processing Requirements: Some materials require extensive post-processing, increasing time and cost.
Budget Constraints: Material costs vary significantly, from inexpensive filaments to premium metals.
For specialized applications like medical devices, additional factors such as biocompatibility and sterilization capability become critical, while aerospace applications may prioritize weight, strength, and thermal stability9.
Understanding the costs involved in rapid prototyping is crucial for effective financial planning, resource management, and overall decision-making throughout the product development process4.
Material is one of the three main factors directly influencing prototyping costs. As a rough estimate, SLA materials start from $0.4 per gram and SLS (Nylon) from $0.7 per gram. In comparison, stock billets of material for CNC prototyping range from around $3 per kilogram up to over $200 per kilogram.
The material cost varies depending on:
Material type (standard vs. specialty)
Material quality (medical grade, aerospace grade, etc.)
Quantity required
Wastage during the printing process
Labor costs include:
Skilled technician wages
Design and engineering time
Post-processing labor
Quality control and inspection
For different materials and technologies, distinct cost-per-hour rates are often applied. More complex prints or those requiring extensive post-processing will incur higher labor costs.
These include:
Depreciation of 3D printing equipment
Maintenance and calibration
Energy consumption
Software licenses
Facility costs
A simple prototype can cost anywhere from $50 to $500, while larger metal parts might escalate into several thousand dollars per iteration4. Cost increases with:
Size of the prototype
Complexity of geometry
Required precision
Number of iterations
Design Optimization: Design parts specifically for additive manufacturing to reduce material usage and print time.
Batch Production: When possible, print multiple prototypes simultaneously to share setup costs.
Material Selection: Choose appropriate materials based on the specific requirements rather than defaulting to premium materials.
Technology Selection: Select the most cost-effective technology for each stage of prototyping (e.g., using FDM for early concepts before moving to SLA for detailed prototypes).
Iteration Planning: Carefully plan iterations to minimize the number of physical prototypes required.
Simulation and Virtual Testing: Use digital simulation before physical prototyping to identify potential issues early.
The medical field has embraced rapid prototyping for numerous applications, from customized prosthetics to surgical planning models and medical device development.
During the first wave of the COVID-19 pandemic, mechanical engineer Mike Dresher collaborated with his brother, Dr. Brad Dresher, along with AGCO engineer Dr. Steve O’Halloran and respiratory specialist Rob Scott, to rapidly prototype a ventilator valve splitter. With ventilators in short supply, creating a tool to split the airflow from one ventilator to multiple patients could exponentially increase hospital ventilator capacity.
The team used Xometry’s 3D printing capabilities to test proof-of-concept snap fits with ventilator tubing and to find the optimal combination of material and mechanical properties. They cycled through multiple printing technologies:
Initially selecting HP Multi Jet Fusion (HP MJF) for its precision and affordable price
Switching to FDM when concerns about chemical inertness of MJF materials arose
Finally settling on SLS with nylon material (PA2200) that had passed USP Class VI biocompatibility per FDA requirements5
Within just 20 days, the team had quoted, revised, and received 9 prototype iterations, demonstrating the incredible speed and flexibility of rapid prototyping for medical innovation during a crisis.
Beyond emergency applications, rapid prototyping has revolutionized personalized medicine through:
Patient-Specific Implants: Using patient CT or MRI data to create perfectly fitted implants for craniofacial reconstruction, hip replacements, and dental applications.
Surgical Planning Models: Creating physical representations of a patient’s anatomy to allow surgeons to practice complex procedures before operating.
Custom Surgical Guides: Producing tools that match a patient’s unique anatomy to improve surgical precision and reduce operating time.
The aerospace industry has been at the forefront of adopting rapid prototyping for both development and production applications.
AeroCo, a highly innovative aerospace firm, undertook a journey to scale additive manufacturing from rapid prototyping to high-volume production. This transition required significant realignment of existing technology and product development processes.
To achieve this alignment, AeroCo formed institutional alliances with the UK government and universities to establish:
University technology centers that facilitated early-stage ideation
“Catapult” centers that enabled high-volume testing in factory-like facilities
The case reveals how multiple functions needed to integrate, including research and development, product design, and future programs, to ensure that design changes cascaded properly throughout the product ecosystem.
Rapid prototyping enables aerospace manufacturers to create:
Lightweight Structural Components: Complex geometries with internal lattice structures that reduce weight while maintaining strength.
Integrated Assemblies: Parts that would traditionally require multiple components and assembly steps can be printed as a single unit.
Heat Exchangers and Fluid Systems: Intricate internal channels and geometries impossible to manufacture with traditional methods.
Tool and Fixture Creation: Custom jigs and fixtures for assembly and testing processes.
Consumer products benefit tremendously from rapid prototyping through accelerated development cycles and enhanced design freedom.
A novel functional rapid prototyping process combines 3D printing and Augmented Reality to create interactive prototypes. These prototypes interpret user gestures on the physical 3D-printed model, converting clicks and touches into actions executed on the AR virtual prototype.
This approach enables:
Early user experience testing
Functional validation without complete electronics integration
Rapid iteration of both physical form and interaction design
More comprehensive user feedback before final tooling investment
Rapid prototyping accelerates development of numerous consumer products:
Smartphone Cases and Accessories: Creating ergonomic prototypes to test grip, button accessibility, and aesthetic appeal before mass production.
Kitchen Appliance Housings: Testing different handle designs, button layouts, and visual elements with functional prototypes.
Toy Development: Rapidly iterating designs based on safety testing and child interaction studies.
Packaging Prototypes: Creating physical mockups of packaging designs to evaluate functionality, aesthetic appeal, and shelf presence.
The rapid prototyping process typically follows these fundamental steps:
CAD Model Creation: Develop a 3D digital model using CAD software, or acquire one through 3D scanning and photogrammetry. CAD models typically result in fewer errors and can be corrected before printing.
Geometry Validation: Ensure the model represents a valid geometric form with properly enclosed surfaces and no internal errors that would affect printing.
File Conversion: Convert the CAD model to STL format (or newer formats like AMF), which represents the surface geometry as triangulations and serves as the de facto standard for additive manufacturing.
Slicing: Process the STL file through slicing software, which converts the model into thin layers and produces G-code or other machine instructions tailored to the specific 3D printer type.
Printing: Execute the print job using the appropriate technology, materials, and settings based on the prototype requirements.
Post-Processing: Perform necessary cleaning, curing, support removal, surface finishing, and other treatments to complete the prototype.
Validation and Testing: Evaluate the prototype against design requirements and functional specifications, gathering feedback for the next iteration.
Design for Additive Manufacturing (DfAM): Incorporate overhangs of less than 45 degrees when possible, add appropriate wall thicknesses (typically 1-2mm for most technologies), and include drainage holes for resin prints.
Topology Optimization: Use specialized software to create organically optimized structures that minimize material while maintaining functional requirements.
Part Consolidation: Redesign multi-component assemblies as single parts where appropriate, eliminating assembly steps and potential points of failure.
Orientation Planning: Design with print orientation in mind to minimize support structures and optimize mechanical properties.
Function-Driven Selection: Choose materials based on the specific functional requirements rather than default preferences.
Prototyping Progression: Use less expensive materials for early concept validation before moving to higher-performance materials for functional testing.
End-Use Consideration: For prototypes that will undergo user testing, select materials that closely mimic the properties of production materials.
Multi-Material Approaches: Consider using different processes and materials for different components based on their specific requirements.
The “fail fast” method is used to test hypotheses, build trial designs, and experiment without significant time and financial investment. This approach speeds up product development by providing business and engineering feedback early, before major investments like injection mold tooling.
Key elements of this approach include:
Rapid Iterations: Plan for multiple quick iterations rather than attempting perfection in early prototypes.
Incremental Testing: Test specific aspects or features in isolation before combining them into more complex prototypes.
Parallel Prototyping: Develop multiple design variants simultaneously to compare performance and features.
User Feedback Integration: Incorporate user testing early and often, using insights to drive the next iteration.
Documentation: Maintain detailed records of each iteration, noting what worked, what failed, and why changes were made.
This method is particularly valuable for startups and new product development, where uncertainty is high and resources may be limited.
Researchers are exploring additive manufacturing as a tool for rapid design and fabrication of specialized laboratory equipment. In one proof-of-concept study, scientists developed a 3D-printed prototype crystallizer for pharmaceutical applications.
Traditional fabrication technologies limit the possibilities for easy and rapid lab-scale design, fabrication, and testing of crystallizer design variants. Additive manufacturing overcomes these challenges by providing:
Flexibility in design
Ability to rapidly redesign and prototype novel configurations
Lower cost for creating specialized equipment
Customization for specific experimental requirements
The researchers demonstrated how 3D printing could be used to create down-scaled crystallizers based on classic designs, with subsequent modifications made rapidly to optimize performance.
The integration of rapid prototyping with other technologies is creating new possibilities for interactive prototyping. One innovative approach combines 3D printing with Augmented Reality (AR) to create functional interactive prototypes.
These prototypes interpret user gestures on the physical prototype, converting clicks and touches into actions executed on the AR virtual prototype. This makes the prototype both functional and interactive without requiring complete electronic integration.
Benefits of this approach include:
Reduced development time and cost
Earlier user experience testing
More comprehensive feedback
Flexibility to rapidly adjust both physical and digital interactions
As 3D printing technologies mature, rapid prototyping techniques are increasingly being used not just for prototyping but also for bridge production and low-volume manufacturing:
Bridge Production: Using 3D printing to produce initial product runs while traditional tooling is being developed, allowing companies to enter the market faster.
Low-Volume Custom Products: Creating economically viable small production runs of customized products without the high fixed costs of traditional manufacturing.
Spare Parts on Demand: Printing replacement parts for legacy equipment or low-demand components, reducing inventory costs.
Localized Manufacturing: Distributing production closer to the point of use, reducing shipping costs and delivery times.
It has been shown that it is economically feasible to use existing commercial Rapid Prototyping systems to manufacture series parts in quantities of up to 20,000 and customized parts in quantities of hundreds of thousands.
The field of rapid prototyping continues to evolve rapidly, with several key trends shaping its future:
High-Performance Polymers: Development of engineering-grade thermoplastics with improved heat resistance, strength, and durability.
Metal-Polymer Composites: Materials that combine the printability of polymers with properties closer to metals.
Bio-Based and Sustainable Materials: Environmentally friendly alternatives derived from renewable resources.
Gradient and Functionally Graded Materials: Materials that can transition properties within a single part, creating zones with different characteristics.
Increased Print Speeds: Technologies like Carbon’s CLIP (Continuous Liquid Interface Production) and HP’s Multi Jet Fusion are dramatically reducing print times.
Higher Resolution: Advances in hardware and software enabling more precise feature definition and smoother surfaces.
In-Process Monitoring: Real-time quality control using cameras, sensors, and machine learning to detect and correct errors during printing.
Hybrid Manufacturing: Combining additive and subtractive processes in single machines for greater flexibility and precision.
AI-Driven Design Optimization: Artificial intelligence algorithms that automatically generate and optimize designs for additive manufacturing.
Digital Twins: Virtual replicas of physical products that can be used for simulation and testing before physical prototyping.
Extended Reality (XR) Integration: Combining physical prototypes with virtual and augmented reality for comprehensive product evaluation.
Blockchain for Digital Rights: Technologies to protect intellectual property and ensure authorized manufacturing as distributed production becomes more common.
Rapid prototyping in 3D printing represents a fundamental shift in how products are conceived, developed, and manufactured. From its origins as a visualization tool for concept models, it has evolved into a sophisticated ecosystem of technologies capable of producing functional prototypes and even end-use parts across diverse industries.
The integration of advanced CAD modeling, increasingly sophisticated printing technologies, and an expanding range of materials has democratized product development, allowing smaller companies and individual innovators to compete with larger enterprises by dramatically reducing development time and costs. The ability to quickly iterate designs based on testing and feedback has transformed the product development lifecycle, enabling a more agile, responsive approach to innovation.
As we’ve seen through various case studies—from emergency medical devices created during the COVID-19 pandemic to aerospace components transitioning from prototypes to production parts—rapid prototyping offers tangible benefits in nearly every industry. The ability to create complex geometries impossible with traditional manufacturing, combined with the economic viability of small production runs, has opened new possibilities for customization and optimization.
Looking forward, the continued convergence of rapid prototyping with other technologies—artificial intelligence, augmented reality, advanced materials science, and digital manufacturing platforms—promises to further accelerate innovation and enable new applications we can only begin to imagine. The “fail fast” methodology enabled by rapid prototyping will likely become standard practice across industries, promoting a culture of experimentation and continuous improvement.
For businesses, designers, engineers, and innovators looking to leverage these capabilities, understanding the technologies, materials, processes, and best practices of rapid prototyping is no longer optional but essential. Those who master these tools will be positioned to lead in an era where speed to market, customization, and design optimization are critical competitive advantages.
Interactive rapid prototyping combining 3D Printing and Augmented Reality
Authors: Derzu Omaia, Walter Franklin Marques Correia, André L. M. Santos
Journal: J. Interact. Syst.
Publication Date: 2024
Key Findings: Proposed a new functional rapid prototyping process combining 3D Printing and AR to create functional interactive prototypes
Methodology: User gesture interpretation on physical prototypes converted to actions in AR virtual prototypes
Citation: Omaia et al., 2024, pp. 20-35
https://www.semanticscholar.org/paper/Interactive-rapid-prototyping-combining-3D-Printing-Omaia-Correia/d6bc946bc838596861836ea56071cf1270dafb9d
Transitioning additive manufacturing from rapid prototyping to high-volume production: A case study of complex final products
Authors: [Authors not fully provided in search results]
Journal: Journal of Product Innovation Management
Publication Date: 2023
Key Findings: Identified key factors enabling the scaling of additive manufacturing from rapid prototyping to high-volume production
Methodology: Longitudinal case study of AeroCo, collecting primary and secondary data
Citation: [Full citation not available in search results], 2023
https://onlinelibrary.wiley.com/doi/10.1111/jpim.12673
Additive Manufacturing as a Rapid Prototyping and Fabrication Tool for Laboratory Crystallizers─A Proof-of-Concept Study
Authors: Nico Nys, Michael König, Peter Neugebauer, Matthew J. Jones, Heidrun Gruber-Woelfler
Journal: Organic Process Research & Development
Publication Date: 2023
Key Findings: Presented a concept study for a 3D-printed prototype crystallizer
Methodology: Discussed additive manufacturing as a tool for rapid design and fabrication of down-scaled crystallizers
Citation: Nys et al., 2023
https://pubs.acs.org/doi/abs/10.1021/acs.oprd.3c00126
Rapid prototyping
Keywords: Manufacturing techniques, 3D printing, CAD modeling
https://en.wikipedia.org/wiki/Rapid_prototyping
3D printing
Keywords: Additive manufacturing, Digital fabrication, Layer manufacturing
https://en.wikipedia.org/wiki/3D_printing
Q1: What is rapid prototyping and how does it relate to 3D printing?
A1: Rapid prototyping is a group of techniques used to quickly fabricate a scale model of a physical part or assembly using three-dimensional computer aided design (CAD) data. 3D printing is one of the primary technologies used to implement rapid prototyping. In the 1980s, 3D printing was primarily used for rapid prototyping, but today, with technological advancements, 3D printing has evolved into a viable production technology, while rapid prototyping remains one of its main applications.
Q2: What are the main cost factors in rapid prototyping?
A2: The main cost factors in rapid prototyping include material costs (depending on type, quality, and quantity), labor costs (skilled workers, wages, and operation time), equipment costs (investment and maintenance of 3D printers or other equipment), and iteration costs (each design change requiring a new prototype). A simple prototype may cost between $50-500, while complex metal parts may cost several thousand dollars per iteration.
Q3: What is the “fail fast” method and what role does it play in prototyping?
A3: The “fail fast” method is a product development strategy used to test hypotheses, build trial designs, and experiment without significant time and financial investment. In prototyping, this approach allows developers to quickly create and test multiple design iterations to identify issues an