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Life-casting limbs

Hand cast.

1: Materials     2: Casting     3: Separation    4: Making a positive  5: Removal

 

Preparation

Casting can be a messy business.
We work mostly in the city of London (which is infamous for having a wide variety of weather).  Many of the products we use for casting are sensitive to environmental conditions.  And, since the comfort of our client is also important; we do most of our lifecasting in doors.
For this reason, it makes sense to prepare your work area with this in mind.

- If located away from the studio (e.g. in a residential home), try to pick a room such as a kitchen or bathroom with easy access to a fawcett.
- Consider that a single application of polythine (or even a few layers of newspaper) on your work surfaces and  floor, will assist your later when it comes to cleaning up after yourself.
- Try to define separate 'wet' and 'dry' areas.  This will prevent you cross contaminating your dry products with water.
Cut lots of managable strips of plaster bandage in advance (while your hands are still dry, and you are not pressed for time).

 

Ask your subject to make themselves comfortable in the required position needed to take the cast.  The whole process could take a while, so you may wish to do a 'dry run' first - making your subject remain motionless in that pose for 3-5 mins.

For best results, follow the manufacturers directions when mixing the alginate impression cream.
Generally, you should always add powder to water and never the other way around.   This is because the powder sinks naturally to the bottom and is less likely to trap air when mixed.

When you have achieved a smooth creamy paste, begin applying it starting from the top.  Initially you will be running a gauntlet - attempting to keep the alginate from running right off! - but as you continue to keep moving the product around the whole area, changes in the melecular structure of the alginate will make it more sticky and less fluid.

Applied alginate to the hand and arm.

Since we will be adding a second (structural) skin of plaster bandage, a coating of between 6-12mm of alginate is normally sufficient (less is possible, but on a larger piece you risk losing structural integrity), you should consider the possibility that when you come to separating the moulds, you may be forced to use sharps.  Bearing this in mind, you will want to create as much distance as possible between the bandage you are cutting and your subject's skin by making sure that your alginate layer is thicker than usual (just to play safe).

Avoid the temptation to smooth the alginate - an uneven surface will create a better key for the strips of wetted plaster bandage to adhere to.   You will need to apply enough plaster bandage to create a strong support for the alginate, once your arm is removed; but not so much that you add unnessessary weight, and have more to cut through.

 

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  S y l a k    S p e c i a l   E f f e c t s

Sculptor / Model maker: Sylak  -   Make-up artist / Painter: Nicky
Assistant concept designer: Curt.

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This page was last reviewed by the WebMaster on 25/11/2000