Laminated object manufacturing (LOM) is a method of 3D printing. It was developed by the California-based Helisys Inc. (now Cubic Technologies). During the LOM process, layers of plastic or paper are fused or laminated together using heat and pressure, and then cut into the desired shape with a computer-controlled laser or blade. While LOM is not the most popular method of 3D printing used today, it is still one of the fastest and most affordable ways to create 3D prototypes.

Process of Laminated Object Manufacturing

Like all 3D-printed objects, models made with an LOM system start out as CAD files. Before a model is printed, its CAD file must be converted to a format that a 3D printer can understand usually STL or 3DS.

An LOM apparatus uses a continuous sheet of material plastic, paper or (less commonly) metal which is drawn across a build platform by a system of feed rollers. Plastic and paper build materials are often coated with an adhesive. To form an object, a heated roller is passed over the sheet of material on the build platform, melting its adhesive and pressing it onto the platform. A computer-controlled laser or blade then cuts the material into the desired pattern. The laser also slices up any excess material in a crosshatch pattern, making it easier to remove once the object is fully printed.

After one layer of the object is formed, the build platform is lowered by about one-sixteenth of an inch the typical thickness of one layer. New material is then pulled across the platform and the heated roller again passes over the material, binding the new layer to the one beneath it. This process is repeated until the entire object has been formed.

Once an object is done "printing," it is removed from the build platform, and any excess material is cut away. Objects printed in paper take on wood-like properties, and can be sanded or finished accordingly. Paper objects are usually sealed with a paint or lacquer to keep out moisture.

Advantages

The LOM process doesn't involve any chemical reactions, no enclosed chamber is needed, making it easier to build large models. The materials used during LOM are also inexpensive, consistent, readily available and well understood.

Disadvantage

LOM is not ideal for creating objects with complex geometries, and it can't create hollow objects. Because this process doesn't produce highly accurate parts, it can't be used to create functional prototypes. For this reason, LOM is used primarily for creating scaled models and conceptual prototypes that can be tested for form or design.