Rapid Prototyping - One-of-a-Kinds

Rapid prototyping describes the method of producing a part by building up layer upon layer of material to create a finished prototype. The produced parts typically look like a deck of cards and will require some finish work to sand and smooth the surfaces. The parts can then be painted to resemble a production-ready part. While this method works great for 1-5 units, if you require larger quantities you should consider using a different method to lower costs and increase consistency. All of the following solutions are rapid prototypes: 3 dimension printing, fused deposition modeling (FDM), laminated object manufacturing, selective laser sintering and Stereo lithography (SLA).

Rapid Tooling – Few-of-a-Kinds

Rapid tooling uses a rapid prototyped part to develop a simple mold to be used for small-scale prototyping runs. The mold provides the ability to use plastic injection to create the part and some mold materials will produce up to a 100 units without failure. The only catch here is that you will have to pay extra for the mold development and this will increase the time to develop the products.

Rapid Injection Molding – Some-of-a-Kinds

This approach uses your CAD model to mill out a metal mold that can be used for injection molding of your product. The choice of materials for the part is significantly broader than rapid tooling and will allow for small-scale production runs of up to 5,000 units. This can be a cheap and quick alternative to developing a traditional injection mold and a better solution than rapid tooling due to greater longevity and quality of the product. The costs for mold development can be in the thousands but unit production costs will be cheaper.

Table from IDES "Plastic Prototyping: How Methods Measure Up" by Brad Cleveland.

---