You will need
- - shield;
- lubricant (oil or vaseline);
- - dry paint;
- - dry plaster of fine and coarse grinding;
- - a metal fork or comb.
If you need to make a form on the basis of clay, plasticine or plaster model, use gypsum. Please note that this form will be disposable, rough.
Dilute the first coat: take 3-7 grams of dry paint, 1 liter of water and a little gypsum mortar, stir until a homogeneous dense mass. Note that the excess paint will lead to the softening of the plaster and the difficulty of raskulachivanija form.
For the second layer forms a rough plaster head coarse. Dilute a quantity of the mixture sufficient to cover models 30 mm (for large models – not less than 50 mm).
Find a shield and cover it with a lubricant (oil or vaseline), spray model lightly with water. Secure the model on the shield in a horizontal position.
If the model from clay, treat with moisturizing matte shade and a small soft. Note that dry clay is able to absorb water and increase volume. Therefore, remove the excess water from the grooves with a brush.
Apply the first color layer of plaster and spread it evenly with a shovel or hand across the surface. Ensure that the plaster fills all the cavities and irregularities. Spread the plaster in one direction, to be able to regulate the layer thickness (3-8 mm).
Once the solution begins to solidify, quickly protsarapat the surface of the metal with a fork or comb (to make the layers better grabbed). To consolidate the form can attach a wire armature, it's okay if she's going to play out.
After full curing of the first layer apply a second layer of plaster. First, distribute the required amount with a spatula, then spread, if necessary, adding new portions.
When the form for the plaster completely hardens, remove it from the model. To gently insert the wooden wedges and pour a little water (it will help to soften the clay). Gradually undermines the model in the form, insert new wedges, again add some water. After a while you will be able to remove a plaster mold without damaging the model.
Clear the form from the remnants of clay, rinse under running water. To make it easier to use, coat the inner surface with birch liquor or spirit varnish.