Seating cork pads is an art that requires skill, practice, patience and the perfect cork material. The pad will first be glued into the pad cup with shellac and then ground to the precise angle. Pads with a center hole can be especially difficult to seat in this way. Using this method, the pad does not become misshapen due to overheating and the surface is perfectly straight and smooth. The expected lifetime can be as many as 10 to 15 years.