Cable Tray Below a Beam with Side-Wall Clearance

Reference the underside to the incoming base

This route descends below a hanging beam, passes beneath it and rises back to the incoming tray level. Measure the beam underside as a positive downward distance from the incoming base plane. Measure beam length along the route. Enter the clearance above the highest part of the tray side wall.

The example places the beam underside 150 mm below the incoming base. Clearance is 50 mm and tray side height is 50 mm. The lower base must drop by 150 + 50 + 50 = 250 mm. At that level the wall top is 200 mm below the incoming base, giving the requested 50 mm gap below the beam.

Use a 200 mm wide tray, 400 mm beam length, 45° slopes and 350 mm lead and tail. Side height is part of this vertical clearance calculation. Locate both wall tops in the formed side view before transferring the dimensions to material.

Calculate both slopes and the lower middle section

For base-level drop R and slope angle θ, each sloped base length is S = R / sin θ and its horizontal projection is Q = R / tan θ. With R = 250 mm and θ = 45°, S = 353.55 mm and Q = 250 mm. Both diagonal base sections have the same length.

The lower middle axis spacing is P = O + 2[c + h tan(θ/2)], using beam length O, clearance c and wall height h. Here P = 400 + 2[50 + 50 tan 22.5°] = 541.42 mm. The lead, two slopes, middle and tail add to 1948.53 mm of straight stock.

Worked example dimensions

Inspect the opening and closing joint pairs

The stock stations are 350, 703.55, 1244.97 and 1598.53 mm, with turn sequence −45°, +45°, +45°, −45°. Folds 1 and 4 open side-wall slits during forming. Folds 2 and 3 close side-wall V cuts. Preserve the base connections shown at all four joints.

At the closing pair the full V width is 2h tan(θ/2) = 41.42 mm. At the opening pair the fully formed wall-top gap is 2h sin(θ/2) = 38.27 mm. Follow Original, Mark, Cut and Form to read each measurement at its corresponding stage, then check the complete wall profile below the beam.

Review the fabrication detail

The route uses ideal sharp folds. Check the actual profile, lips, material allowances, joint covers and the space required by the cable path against the product instructions and site dimensions.