Lifecasting

Lifecasting is the process of creating a three-dimensional copy of a living human body, through the use of molding and casting techniques. In rare cases lifecasting is also practiced on living animals. The most common lifecasts are of torsoes, pregnant bellies, hands, faces, and genitalia and it is possible for an experienced lifecasting practitioner to copy any part of the body. Lifecasting is usually limited to a section of the body at a time, but full-body lifecasts are achievable too. Compared with other three-dimensional representations of humans, the standout feature of lifecasts is their high level of realism and detail. Lifecasts can replicate details as small as fingerprints and pores.

There are a variety of lifecasting techniques which differ to some degree; the following steps illustrate a general and simplified outline of the process:

A variety of materials can be used for both the molding and casting stages of the lifecasting process. For molding, alginate, and plaster bandages are the most popular materials. Less common mold materials are silicones, waxes, gelatins, and plaster. Plaster and gypsum cement are the most commonly used casting materials, but various clays, concretes, plastics and metals are also in common use. Ice, glass, and even chocolate are used often as casting materials. Work is being done with imaging technology to map the skin's surface which may enable re-creation of the shape without touching the body. Since the weight of material deforms the body, if only slightly, this new technique may enable even more perfect work, but will not give the skin texture the above-listed materials do.

Compared to the molding of inanimate objects, lifecasting poses some specific challenges and risks. Since the mold is made directly on the skin of the model, for safety and health reasons the molding materials must be non-toxic. The mold must not heat up too much or else discomfort and even severe burns could occur. The molding process must also be completed within a relatively short time frame, usually a half-hour or less, since people have limited endurance in holding a stationary pose. Methods to allow the model to continue breathing must also be used when a mold covers the mouth and nostrils. (Generally the nostrils are kept clear, but not with straws.) If the model is captured with lungs deflated it will be impossible to take a deep breath. To prevent injury or trapping the model in the mold, the shape and position of the mold must be well planned prior to application.

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