Atelier - Acrylic Mediums - 250ml - Modelling Compound - Atelier Interactive Modelling Compound can be used for building impasto areas during any stage of the painting process. It dries to a white satin finish and remains flexible. Also ideal as a ground preparation on canvas, paper or other painting surfaces. Modeling Compound may be added to Atelier Acrylic as an economical extender. For more textured effects, sawdust, sand, etc may be added.