A method of protecting a hole in a component during a coating process is disclosed. The method includes: placing a plug in the hole, the plug including a water insoluble core and a water soluble layer surrounding at least a portion of an outer surface of the metal core. A coating is applied over the plug and at least a portion of the component. The component is immersed in water to dissolve the water soluble layer, allowing removal of the water insoluble core. Removal of the coating from over the hole and the water insoluble core from within the hole may follow.