The LTT 621 is controlled by a programmable controller, which makes operation user-friendly. The operator inputs the radius of the work piece, and a beam automatically finds the centerpoint where polishing should begin. Work piece minimum length is 270 mm (10.6 inches) and minimum width is 200 mm (7.87 inches). Work pieces travel on a conveyor belt at 45 to 60 feet per hour for efficient processing.
The LTT 621 offers many features, including a calibration mandrel to gauge thickness at an adjustable depth (maximum 6 cm). The mandrel can be adjusted both horizontally and vertically. It can rotate 0 to 90 degrees, and can be used to carry out slotting for the drip stone. Motor power is 3.6 KW (5 HP); rotation speed is 1,400 RPM.