The Different Rapid Prototyping Techniques

When designing a product, every engineer or producer dreams for the final product to be a success; a bad design usually results in nonfunctional parts and outrageous production costs. For this reason, it is best to test different components and refine your ideas; this provides a clear pathway from concept to reality. Rapid prototyping offers product designers valuable insights before allocating too many resources to an idea with little chance of success.

What is rapid prototyping?

Rapid prototyping is the fast fabrication or creation of a physical part, model, or assembly, from its computer-aided design using various manufacturing techniques. It is a vital process in product development and can be used at any stage for any components or subcomponents. Rapid prototyping enables the creation of functional and successful products. It is a crucial element of new product development as manufacturers and producers can test the practicality of the parts before introducing them to the market.

Types of rapid prototypes

Understanding the types of prototypes in product design is essential before outsourcing rapid prototyping services for your design. Usually, rapid prototyping is for single parts rather than assembled parts. Therefore, an assembly can constitute several rapid prototyped parts, or a single one can be used to test and evaluate a model. Different types of prototypes are categorized based on the degree of accuracy required, purpose and product development stage.

Rapid prototypes don’t always look like final products; their appearance can vary depending on what the designer aims to achieve from the prototype. When classifying rapid prototypes, accuracy or fidelity is a variable to consider. A design that closely matches the final product’s appearance and function is said to be a high-fidelity prototype. On the other hand, a product is an aid to be low-fidelity when there is a marked difference between the prototype and the final product.

Rapid prototyping techniques

The rapid prototyping technology you use significantly determines the success of your prototype. For this reason, you want to choose a suitable method for the success of your product development. There are several techniques, and each has its compromise in terms of cost, material compatibility, speed, accuracy or fidelity level and development stage. Examples of rapid prototyping technology available for engineering product designers include:

·         Additive manufacturing. This includes selective laser sintering (SLS), stereolithography (SLA), fused deposition modeling (FDM), direct metal laser sintering (DMLS), and poly jetting.

Although most manufacturing techniques utilize layered additive manufacturing, other technologies, such as casting, molding, high-speed machining, and extruding, can be used for rapid prototyping. Here is a detailed discussion of the rapid prototyping techniques


Stereolithography involves using laser energy to solidify or cure UV-curable resin to build parts from a pool of photosensitive liquid. The technique is suitable for lower-end functional prototypes, molds, patterns and production tools.

SLA allows product designers and engineers to produce rapid prototype parts with good dimensional accuracy and excellent surface finish. The process is also fast and affordable and offers a comprehensive material selection. However, SLA has low strength than other AM techniques; this limits some functional testing. The resin can also become brittle over time.

Selective laser sintering

Selective laser sintering uses polymer powder and laser energy to build a prototype one layer at a time. The technique can be used for metal and plastic prototyping; the resulting parts have internal porosity and excellent tensile strength. SLS has a higher build volume and can produce or generate long-lasting complex designs. While this technique requires no support structure and is suitable for dying and coloring, it also has its limitations. For example, it has a limited choice of resin material and produces prototypes with a rough surface finish.

Direct metal laser sintering

This additive manufacturing technology uses a computer-controlled, high-power laser beam to melt and fuse layers of metallic powder. Since most alloys can be used in DMLS, the strength of prototypes is guaranteed. The technique also produces shapes and features that are difficult to achieve with conventional CNC machining. On the downside, the method is one of the slowest, expensive and requires a specialized manufacturer.

Fused deposition modeling (FDM)

Fused deposition modeling involves melting thermoplastic filament inside a printing nozzle barrel, then layering down the liquid layer by layer, according to a computer design program. Initially, the resulting prototypes were weak and had poor resolution. However, the process is improving rapidly and is fast and cheap, making it ideal for product development.

Rapid prototyping helps you make the most out of your product development. Even so, you want to work with professionals to eliminate the risk of product failure.