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. When a wire cable tray is cut, the fact that a. Elbow joint RVS is pushed inside the cable tray and attached with the included screw set. For example, use 100mm gaps for 100mm. The production of cable tray elbows requires the following steps: 1. Determine the angle and required radius size of the elbow, and choose the appropriate elbow type based on these parameters, such as 90 degree elbow, 45 degree elbow, etc.