I demonstrated to my beginning throwing students on how to apply cone 10 glazes by dipping and pouring on their bisque ware. A student noticed after the application was dried, there was small bubble/blisters on the glazed surface. I told students to leave the surface alone and hope the glaze firing will melt and smooth away the bubbles. I also showed them how to use their finger to gently rub away the bubbles.
The next day, I found one of my students trying to sand away the bubbles with