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.
A company called Helisys (which was succeeded by an organisation called Cubic Technologies) created laminated object manufacturing in 1991. Helisys fused sheets of material together before using a digitally guided laser to cut out the desired object, although they ended operations in 2000.
Brothers Conor and Fintan MacCormack developed the original process in 2003 by using standard office paper and an inkjet printer to print the designs. The paper was then built up layer-by-layer before a tungsten blade is used to cut away the waste paper to reveal the final object.
The MacCormack brothers commercialised LOM through their company, Mcor Technologies, which continued to develop the process by using CMYK colour to print more vivid objects that could be used for promotion or visual prototyping. This new process was developed so that sheets of paper were colour printed before being selectively glued and cut. In this process, known as selective deposition lamination (SDL), the adhesive is only applied to the areas that correspond with the design, making the final object easier to cut from the waste material.
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.
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.
Despite the challenges and disadvantages of LOM, the process remains an excellent option for conceptual prototyping due to the speed and low cost of the process.
Scale models can also be created using laminated object manufacturing, while the use of colour inks and paper also allows for the creation of inexpensive yet eye-catching 3D promotional items.
While the final results of laminated object manufacturing mean that items created using this technique are rarely used as finished products, LOM is a highly time and cost-effective method for creating rapid visual prototypes to test designs.
LOM can be used with a range of different materials to create prototypes, models and even inexpensive promotional items, making it an efficient technique for a range of different industries.
Related Frequently Asked Questions (FAQs)