Laminated Object
Manufacturing
"LOM"
(overview)
Laminated Object Manufacturing
is a Rapid Prototyping and Manufacturing process
that uses a carbon-dioxide laser to create successive
cross-sections of a three-dimensional object from
layers of paper with a polyethylene coating on
the backside. The first step is to create a base
on which the paper can attach itself to. This
is done by placing a special tape down onto the
platform. A sheet of paper is feed through with
the aid of small rollers. As the paper is feed
through, steam is used to heat the coating on
the paper so that each new layer will adhere to
the previous layer.
The carbon-dioxide laser then traces, or etches,
the outline of the cross-sectional pattern into
the top layer of paper. Once the laser is done
etching the pattern, it burns a border into
the paper that contains the etched pattern.
This enables the part to stay intact as each
new layer is created. Once the border has been
traced, the laser then proceeds to create hatch
marks, or cubes that surround the pattern within
the border. The cubes behave as supports for
the part to ensure that no shifting or movement
takes place during the entire build.
When the build is completed, the part, attached
to the platform, needs to be removed from the
LOM. Depending on the size of the part, the
block to be removed may weigh a great amount.
Thus, it may take more than one person to remove
the build from the LOM. After the part has been
successfully removed from the LOM, it must then
be removed for the actual platform. Again this
may take the work of more than one individual.
A wire is used and placed between the part and
the platform to "cut" the part away
from the metal platform. In a similar fashion
to sawing wood from a tree, then wire is moved
back and forth between the part and platform.
This continues until the part is completely
removed.
The border, or frame of the part is then removed.
The next step involves decubing. or removing
the supports. Often times the supports can be
removed from simple shaking the part; other
times it is necessary to use a chisel to pry
the cubes away from the part. When all of the
cubes have been removed, the unfinished part
is sanded down and a lacquer is used to seal
the part. Being that LOM parts are made from
paper, humidity and temperature affect the structure
and composure of the part if it is not coated;
hence, the lacquer serves as a protective measure.
The LOM is very useful in manufacturing large
parts quickly.
|
The term | Simple
