This shows, on the left, a Shire model which has been fettled (i.e.the break lines taken off) and the tail attached. The model on the right has just come out of the mould. The ruler laid across the back shows just how much shrinkage there is between damp and dry.
Although it is not shown in this picture, the thickness of the clay slip as cast is not much more than 3\32 inch or4 mm. If it casts up much thicker than this, there is a danger that the legs at hock and knee might be solid. This would make a dangerously enclosed void in the hoofs. If I feel this has happened, then I poke a needle through the foot into this void so that the trapped air can escape. Before the tail is attached, the flashing between the legs has to be removed. I usually fettle the whole horse before making sure both surfaces, tail and horse, are quite flat and well damped. I put a drill through the mouth for the bit which also acts as a vent hole.

This shows the shrinkage left to right, (1) rubber model, (2) the fettled dry model.(3) The bisque (once fired) model and last, (4) the coloured and glazed fired model. The drop is 2 inches from the original 13 inches.

Allowance for shrinkage must be made in designing the original model, not only height, but also the positions of the feet relative to the body. A heavy model such as this Shire has to be biscuited on a purpose-made stand so that the feet are not left behind as the body shrinks. But a coloured and glazed model has to stand on its own four feet otherwise marks will show.