Creating a 90-degree elbow in an electrical cable tray, often called a "fabricated" or "mitered" bend, involves cutting, bending, and fastening a straight section of tray. The most common method involves creating two 45-degree cuts to form a 90-degree angle. Need more information?Fittings, cable trays, screw connection - Vertical bends, screw connection. Construction of a flat 90° bend (A) The amount of tray lip to be removed is equal to 2, 3/4 the width of the tray, half of this measurement will be removed on either side of the centre line. Choosing the right one depends on project conditions, load. Students trading aid on how best to put an internal 90 degrees bend in steel cable tray.