Abstract: This invention relates to a machine for mixing and blending liquid chemicals with a gas or air, and more particularly for providing an air and chemical mixture having the consistency of a foam substance for coating the surface of a fabric or other substrate material. The invention provides a mixing apparatus having a plurality of peristaltic type pumps that operate at a system pressure that will permit pulsed mixing of air with chemical substances without using high system pressures to achieve a predetermined mix ratio for a chemical compound. The addition of a premix unit helps to achieve the mixing by providing a two stage mixing process when used along with a blending foamer. A unique air injector of the premix unit aids in the initial injection of air into the chemical substance. The blending foamer has an improved rotor configuration and mounting to also achieve enhanced mixing. The mixing apparatus provides a foam substance of a chemical compound for coating a substrate material in a coating machine.