Layer of construction by 3D Printing objects
Within the context of additive manufacture processes, a layer is the individual planar thin section of the object being created. Before being printed, the 3D object's geometry is sliced into a large number of these horizontal sections or layers to be subsequently manufactured in an ordered sequence, with each of the layers adhered to the previous one. The larger the number of layers for a given object, the thinner they are and the higher the vertical resolution of the object produced.
Layers in 3D printing
Although Additive Manufacturing or more specifically 3D Printing could potentially include technologies that don't manufacture layer by layer, in reality pretty much every single technology currently available generates at some point of the process a digitally sliced version of the 3D object to produce. Then, by any of the multiple ways that currently exist ( FDM, SLS , etc) the building material is added giving shape to the first layer, followed by the second layer directly over the first one and so on until the whole object is finished.
The very same nature of this way of creating objects makes from the layer thickness an extremely important parameter to have in mind when 3D printing your designs. If the layers are too thick, the surfaces of any given object will likely to be distorted, showing "steps" instead of a soft, smooth surface. On the contrary, if the layers are too thin, it will take a huge number of layers to build the object, translating into a longer printing time. At then end, there is a trade off between speed and quality that is necessary to adjust based on the user's requirements.
Clockwise from top: 178μm, 28μm and 60μm layers.
At Sculpteo we offer both 100μm and 60μm layers for our plastic material and we can go as low as 28μm layers for our detail resin . Also, not all materials work with any layer thickness and hence choosing the right material for a specific job is key to achieve a satisfactory result.
You can read a bit more about our finest resolution for plastic material on our blog.