Saddle Bend Calculator

Mark the center of the obstruction on the conduit, adjusted for shrink. The center bend is the full saddle angle (usually 45 degrees) and the two outer bends are half that (22.5 degrees). The distance from the center mark to each outer mark = saddle depth x the multiplier for that center angle: the printed bender saddle-table value where a held guide prints one, otherwise the exact 1/sin(outer angle). For a 45 degree saddle the saddle tables print 2.5 per inch of depth, which this calculator applies; exact 1/sin(22.5 degrees) is 2.61. Bend the center first at the full angle, then rotate the conduit 180 degrees and make each outer bend at the half angle.

Saddle mark spacing depends only on the angles and depth, not the conduit size, so 3/4 inch EMT uses the same numbers as 1/2 inch. For a 3-inch deep saddle with a 45 degree center bend: shrink is 3 x 3/16 = 9/16 inch, so place the center mark 9/16 inch past the measured centerline of the pipe (farther from the end you measured from), then put the outer marks 3 x 2.5 = 7.5 inches to each side of center. Choose the depth from the peak the calculator prints for it, not from the pipe diameter alone: on a 45 degree saddle the peak at these marks sits below the entered depth (the saddle table's rounding and the bend radius both take from the top), so a 3 inch saddle in 1/2 inch EMT peaks at 2.54 inches on the centerline, and the conduit's own diameter sits below that.

Use a 4-point saddle when the obstruction is wide or flat: ducts, gutters, I-beams, or anything wider than roughly 4 inches. A 3-point saddle peaks at a single point, so it only clears round obstructions like pipes and other conduits. A 4-point saddle is two opposing offsets that create a flat elevated section, letting the conduit ride level across the full width of the obstruction.

Four bends. A 12-inch I-beam is a wide, flat obstruction, so it calls for a 4-point saddle: two bends to rise, a flat section spanning the beam, and two bends to return. A 3-point saddle would touch the beam only at its peak and would not clear the flanges. This is a common apprentice exam question; the follow-up is usually degree count, and a 4-point saddle at 30 degrees adds 4 x 30 = 120 degrees toward the NEC 360 degree limit.

For a 3-point saddle, shrink = saddle depth x the offset constant for the OUTER angle (half the center angle): 3/16 inch per inch for a 45 degree center and 1/4 inch for 60 degrees. A 30 degree center bends its outers at 15 degrees, an angle no bender manufacturer publishes a shrink constant for, so the calculator works that one from the bend geometry at about 0.132 inch per inch. A 22.5 degree center bends its outer marks at 11.25 degrees, an angle the standard shrink chart does not cover, so there is no trade fraction for it; the calculator works it straight from the bend geometry at about 0.0985 inch per inch. A standard 45 degree saddle over a 3-inch-deep obstruction shrinks the run 9/16 inch, and the center mark moves forward by that same amount. A 4-point saddle behaves like two offsets, so its shrink is double the single-offset value for the bend angle: 3/8 inch per inch of depth at 22.5 degrees.

Add up every bend. A 3-point saddle at 45 degrees center uses 45 + 22.5 + 22.5 = 90 degrees, the same as one 90 degree bend. A 4-point saddle at 22.5 degrees uses 4 x 22.5 = 90 degrees; at 30 degrees it uses 120. NEC 358.26 caps EMT runs at 360 degrees between pull points, so a run with two 90s and a 45 degree 3-point saddle is already at 270 degrees.

The center bend. Align the center mark with the saddle notch or rim notch on your bender (not the arrow), bend to the full center angle, then rotate the conduit 180 degrees and make the two outer bends at the half angle with the marks at the arrow. Keeping all three bends in the same plane matters more than perfect angles; sight down the conduit between bends to check for dog-legs.