Belt plane devices. Planing is recommended for cover rubber thicknesses over 2 mm. The planer allows accurate planing of rubber covers with minimal effort. Planing provides a proven advantage: the belt fasteners are recessed in the belt cover thereby reducing or avoiding the risk of damage to belt fasteners scrapers rollers drive pulleys or tail pulleys.. Belt plane device for frames TS TTN + TTE system (5 - 20 mm).