Rapid prototyping is the process used to generate three dimensional models that do not require any machining or tooling. Instead, it makes use of cutting edge technology that allows a physical object to be formed by adding a material layer by layer until the desired shape is achieved. This allows more flexibility than machining because the complex model designs do not suffer any limitations during the production. Rapid prototyping helps engineers and product designers to generate three dimensional models quickly and accurately. Some popular rapid prototyping services are examined below:
Types of manufacturing: There are two basic types of prototype manufacturing – additive and subtractive. Subtractive process involve older techniques and additive process such as 3D printing is relatively newer and they work by creating layer upon layer until the part is finished.
3D Printing: It is one of the latest processes available. It involves additive process layers of material, usually a plastic or a photopolymer, are built up one at a time over several hours to create parts. Some printers can even use real metal.
Stereolithography (SLA): It is one of the oldest and most popular rapid prototyping techniques that offer a good level of strength, surface detail and cost. This additive process involves a vat of liquid photopolymer. A laser system cures the appropriate sections of each layer.
Selective Laser Sintering (SLS): This process is more expensive and parts often have a rougher finish than SLA but there are a wider range of materials available, including metal, plastic, ceramic and glass.
Urethane Castings: When multiple prototypes are required, it is sometimes more economical to have the parts molded using a urethane casting mode. A master part is usually made using SLA and then a silicone RTV mold is created around it. Then the castings are made from a urethane or polyurethane. These urethanes comes in wide variety and colors.
CNC Machined plastic: Usually CNC mills makes parts using metal such as steel or aluminum, but they can also be used to make prototype parts or low volume parts out of many different kinds of plastic.
Rapid prototype service allows more flexibility than machining and use a variety of materials to create different three dimensional objects. A common material used is prototyping wax which is ideal when engineers and designers require small quantities of casting parts to create intricate patterns without the use of tooling.