They also apply plaster veneer over drywall to create smooth or textured abrasion-resistant finishes. Stucco masons apply durable plasters, such as polymer-based acrylic finishes and stucco to exterior surfaces. Drywall workers and lathers, a related occupation, use drywall instead of plaster, when erecting interior walls and ceilings. They spread this rich plaster mixture into and over the metal lath. Before the plaster sets, plasterers scratch its surface with a rake-like tool to produce ridges, so the subsequent brown coat will bond tightly.
Laborers prepare a thick, smooth plaster for the brown coat.
Plasterers spray or trowel this mixture onto the surface, then finish by smoothing it to an even, level surface. For the finish coat, plasterers prepare a mixture of lime, plaster of Paris, and water. This mixture, which sets very quickly, produces a very smooth, durable finish. Plasterers also work with a plaster material that can be finished in a single coat. This plaster provides a smooth, durable, abrasion resistant finish on interior masonry surfaces, special gypsum baseboard, or drywall prepared with a bonding agent.