Microwave Processing of Polymeric Coatings for Guitar Woods

Microwave energy was used to cure polymer coatings on instrument-grade wood. A processing method was developed that included spray coating the polymer onto raw wood panels and pulling the coated panels through a 2.45GHz multi-mode microwave cavity by means of a low-power motor. Materials characterization and testing used to analyze the feasibility of using microwave processing as a coating method for guitar woods included dielectric property measurements, moisture content measurements, density measurements, and scanning electron microscopy (SEM). Also, vibrational analysis was used to compare the damping characteristics of each coating method, providing further basis for analyzing the feasibility. A comparison was conducted between samples created using the ultraviolet curing method currently used by Taylor Guitar Co. and the microwave samples generated in this study. The results demonstrate that the microwave processing of polymeric coatings for guitar woods is feasible and produces beneficial results. SEM imaging shows enhanced interaction between the polymer and wood in the microwaved samples, which may create a stronger and more durable coating. Vibration testing shows microwave processing produced comparable damping results at half the coating thickness. This decreased coating thickness may lead to a more completely cured polymer, cost savings, and reduce emission during curing.