What is the difference between a poured mould and a brush on mould

With a poured mould you place the original inside a mould box and fill it with liquid silicone. The mould becomes a solid block with the shape of the original left as a cavity. With a brush on mould you apply thickened silicone directly onto the original with a brush or spatula, in several thin layers, until you reach a wall thickness of roughly five to ten millimetres. The mould then becomes a thin skin following the contour of the object.

The main advantage of a brush on mould is material saving. Depending on the shape you use up to eighty percent less silicone. You can also mould objects that would never fit in a mould box, and you can mould on site, for example a wall, a floor or a monument.

The disadvantage is that a brush on mould almost always needs a support shell to hold its shape, and that the technique demands more craftsmanship. The layer build up, the tacky window between layers and how you handle vertical walls determine the quality of the result.

Choose a poured mould for small and flat objects with little volume and for very fine detail. Choose a brush on mould for large or bulky objects, for tub shapes with high side walls, for vertical surfaces and for anything you cannot move.

Read more: complete guide to making a brush on silicone mould