Calendered Solid Pressboards are made on an intermittent board machine using high quality cellulose. The boards are flattened in a hydraulic press, dried, and subsequently calendered to achieve a smooth finish. No bonding agent is added during manufacturing. The entire manufacturing process is monitored and controlled, right from the preparation of pulp to the formation and drying of the sheets. Calendered Solid Pressboards are ideally suited for use in power and distribution transformers as winding cylinders, spacers, strips, etc.