What Is a 3D Rapid Prototype?

Sculpting Michelangelo's David the size of a chess piece is a simple matter for a computer using three-dimensional, or 3D, rapid prototype (RP) technology. Much the same way an inkjet printer produces a two-dimensional image from a digitized file, 3D rapid prototype technology can do the same with actual objects for handling in real space. Relying upon numerous techniques, equipment, and materials, 3D rapid prototype processes generally work from computer-aided drafting (CAD) objects for design or manufacture; they construct them by generating one layer of material at a time until a perfect replica is formed. This construction aids creation of an almost limitless number of complex shapes and objects, revolutionizing design and production efficiency.

Prototyping generally consists of three aspects: constructing models for manufacture, product review, and refinement. Users transform computer schematics directly into prototypes. Designs are evaluated before costly production processes begin, and product surfaces and finishes can be tested.

Manufacturers can customize almost innumerable product shapes for mass production or client customization. Prototype iterations, or variations, can be refined to suit after review from production teams or customers. This permits greater flexibility and lower cost in product development, compared to traditional time-consuming prototyping by machine or hand.

Essentially, the RP process refers to the automated, additive construction of an object; that is, objects are created by adding one sheet, powder, or liquid layer at a time until an object is formed. The making of a 3D rapid prototype refers to high-end manufacture of precision products designed to engineering specifications. Numerous techniques allow the construction of parts, models, and tooling; these can include stereolithography, fused deposition modeling, ultrasonic consolidation, and selective laser sintering, among others. These additive construction methods layer cross sections with techniques like laser fusing, liquid curing, beading, or welding to accommodate specific materials like resins or foils. The use of RP can dramatically cut costs in materials and labor, as well as time; models can be constructed within hours or days.

On a smaller scale, 3D printing is a common technique that is sometimes called 3D rapid prototype construction. This operation, however, uses a smaller desktop machine for design, but lacks the schematic dimensional precision or material versatility of 3D rapid prototype methods used in manufacture. The 3D printer process is typically used for creating throwaway models for hands-on demonstrations, while more complex RP machines possess tooling patterns to aid the production process itself. Additionally, 3D printers may offer only a few material options, while RP can service dozens of materials, such as resins and photopolymers, to duplicate production materials such as thermoplastics.

Rapid prototyping could have long-term implications for industry in the same way the assembly line revolutionized manufacturing. Traditionally, manufacturing costs decrease with time over the lifespan of the product line. With rapid prototyping, the cost to produce only a few units is no different than the cost to produce thousands. While this may help facilitate smaller product counts for custom orders, the potential effects of this condition on how economies of scale are understood are unknown. Manufacturing with 3D rapid prototype technology may continue to fuse design and production stages into more efficient processes.