What is Laminated Object Manufacturing (LOM)?
Laminated object manufacturing is a rapid prototyping process that bonds and cuts sheet material with a computer-controlled laser.
First developed and marketed by California-based Helisys in 1991, LOM emerged as a commercial manufacturing solution the same year Stratasys introduced fused deposition modeling (FDM).Helisys became Cubic Technologies in the year 2000, but is no longer in business.
Mcor Technologies, founded in 2005, was another major LOM hardware company that improved the process by adding full-color capabilities. Its assets were acquired in 2019 by Irish company CleanGreen3D, which continues to develop LOM systems.
LOM technology uses adhesive-coated paper, plastic, or metal laminates as a 3D printing medium. These sheets of material are glued together layer-by-layer and cut into shape using a knife or with laser cutting. Objects created using LOM can then be further modified post process by machining or drilling.
Laminated object manufacturing is a versatile process, which is most usually performed using paper as the material. While plastic and metallic sheets can also be used, these are both more complex to cut.
As an additive manufacturing process, LOM is fast and inexpensive, and is typically used for rapid prototyping rather than production. The precision of the finished object depends upon the thickness of the material layers being used, although it is typically not as precise as other methods.
Though more rudimentary than today’s cutting-edge additive manufacturing processes, LOM offers important benefits like cheap feedstock, colorization, and use in normal working environments such as offices.
How does Laminated Object Manufacturing Work?
Laminated object manufacturing uses a building platform onto which the sheets of material can be rolled out. The materials are usually coated with an adhesive layer that is heated by a feeding roller to melt the adhesive.
In this way, each layer can be glued to the previous one to build up an object. A blade or laser is used to draw out the geometry of the object as well as cross hatching excess material to facilitate the removal of waste.
Once a layer has been glued into place and the required dimensions drawn, the build platform moves down so another layer of material can be rolled into position with the heated roller. This process is repeated until the model or prototype is complete.
If an object is printed using layers of paper it will take on wood-like properties and so may need sanding to finish. Paper objects are then often sealed with paint or lacquer to prevent moisture getting in.
Advantages of Laminated Object Manufacturing
LOM offers several advantages for industry for the quick and inexpensive production of prototypes and other products.
Companies can use a computer-generated model of a product to quickly and efficiently build a prototype from inexpensive build materials like paper, making LOM preferable for rapid prototyping than other manufacturing processes, including 3D printers.
The LOM process can be used to create both solid and hollow objects, including large parts, faster and for less cost than with standard additive manufacturing.
Relatively large parts can be created easily as there is no chemical reaction in the build process, while there is also no need for support material as the laminated material supports itself while curing before the final object is cut out.
Models created with paper have wood-like characteristics, meaning that they can be worked and finished in a similar way.
Disadvantages of Laminated Object Manufacturing
For all of the advantages of LOM, there are still some disadvantages with the process.
Firstly, because LOM is a subtractive process, it is not as easy to produce complex geometric shapes as with other 3D printing processes. This is because it is not always possible to access the internal parts of the object or to remove excess material from within an object.
The nature of LOM makes internal structures and undercuts difficult and can create challenges with breaking parts out from the laminate.
LOM offers reduced dimensional accuracy when compared to stereolithography and selective laser sintering.
Depending on the material used, LOM parts can also have a poor surface finish and more delicate paper parts may have low strength. Paper LOM parts can also readily absorb moisture unless treated.
Pros and Cons of Laminated Object Manufacturing
Laminated object manufacturing offers some highly desirable benefits, including affordability, a large printing envelope, and usability in offices. It also has its drawbacks, such as low accuracy and certain geometrical limitations.
| Pros | Cons |
| Paper feedstock more affordable than typical 3D printing materials | Less dimensionally accurate than most 3D printing processes |
| Machines can be operated in non-industrial environments | Complex internal geometries difficult or impossible to achieve, since material must be manually removed |
| Potential for colorization | Few companies developing hardware; possibility of obsolescence |
| Can fabricate large objects with open build area | Hardware more expensive than FDM |
| Can fabricate overhangs, since preceding layers of material act as a support | Paper parts can absorb unwanted moisture unless carefully treated with sealant |
| Can create composite laminates by alternately layering one material then another | Few users worldwide, making it difficult to find online tips and solutions from other users |
Applications of Laminated Object Manufacturing
Laminated object manufacturing is not a like-for-like replacement for other 3D printing techniques, but it is highly suited to a handful of applications.
In the area of rapid prototyping, LOM represents an affordable route to prototypes of various shapes and sizes. Though not as dimensionally accurate as other additive processes, LOM can be used to fabricate visual prototypes for business proposals, demonstrations, color matching, and other purposes.
LOM systems may be appealing for companies that want to carry out in-house prototyping within an office environment.
The ability to colorize paper LOM parts makes the technology suitable for full-color models such as marketing props, toys, and “3D printed selfies.”
Color 3D printing, which is useful for both decorative and functional objects, has historically been dominated by processes like PolyJet 3D printing from Stratasys.
Some color models may have to be printed on a larger-than-usual scale due to the low level of dimensional accuracy offered by LOM.
Paper LOM 3D printing is an excellent means of making architectural models, which have traditionally often been made by hand from balsa wood.
Laminated paper offers similar material characteristics to wood, but digital fabrication using LOM is much faster and more accurate than manual model making.
Manufacturers carrying out sand casting or investment casting can use LOM to make sacrificial patterns.
An engineer can design a 3D object using CAD software, print it in paper using LOM hardware, then build a sand mold around it. The paper pattern can then be burnt out, creating a cavity within the mold, and the casting material can be poured in.