Solvent-free spraying system including methods and apparatus for spraying plural component materials without requiring the use of solvents to flush out equipment or as part of the materials being dispensed. Materials sprayed can have simultaneously widely varying viscosities, pressures, temperatures and ratios between two or more respective components being combined by the spraying apparatus. Cure rates and gel times can vary widely from hours to less than 10 seconds for mixing and dispensing various plural component thermoplastic and thermosetting materials including foams, moldings and coatings made from urethanes, ureas, epoxies, polyesters, phenolics and other chemical compositions that react rapidly upon mixing of the components thereof.