Making a Simple Plaster Casting Mould

Making a Simple Plaster Casting Mould (back – buttocks)

While the previous step – choosing the ideal pose – is purely artistic, the process of making the casting mould is a precise technical ritual. Only a perfectly made, stable mould can ensure that the final sculpture carries a faithful likeness of the contours and lines.

For casting larger, firm parts of the body, such as the back and buttocks, we most often rely on a proven classic: plaster bandages (gypsum bandages). They create a firm, non-deformable shell, a so-called shell mould, which forms the basis of the future stylised sculpture.

Why plaster bandages?

 

Plaster bandages can be shaped on the body quickly and easily, which makes it possible to keep the time to a minimum and shorten the time during which the model must stay still.

Their main advantages are:

  • Strength: Once cured, plaster bandages form a hard, rigid shell that doesn’t bend or deform. This is crucial when turning the mould over and filling it with the casting compound.
  • Speed: Plaster sets quickly, which minimises waiting time.
  • Weight: They create a light yet extremely strong structure.

Work in the Studio: from the Body to a Simple Mould

Creating a plaster mould is a series of precise and coordinated steps.

1. Preparing the model and the skin

Before casting, the model’s body is carefully prepared. Since plaster is the contact layer, the skin is first treated with a protective greasy cream. All hairy areas are thoroughly treated and the boundaries of the mould are precisely marked on the body.

2. Making and reinforcing the mould

We soak cut pieces of plaster bandage in water and gradually apply them to the body. The pieces are overlapped so that they bond together and form a homogeneous, solid structure.

  • Procedure: We start at the bottom, from the thighs (buttocks), and work evenly upwards to the shoulders. If needed for stability, we apply one more layer of plaster bandages.

  • Handling: Finally, the finished mould is fitted with bamboo sticks. These serve as handles to help us remove the mould later.

3. Removing the mould

After approximately 20 minutes the mould is ready to be removed. Using the handles, the mould is carefully released and taken off the body. Demoulding can easily damage and deform the mould, so the whole process must be extremely careful and slow.

This creates a stable plaster “negative” mould, which is the basis for our next process of stylisation, sanding and smoothing.