Conduit Saddle Bend
Three-point and four-point saddle marks, bend angles, and shrink to clear an obstruction.
Example
You enter
- Saddle type three-point
- Obstruction depth (in) 3
- Bend preset (center/outer) 45/22.5
You get
- Mark spacing 7.5
- Shrink (in) 0.5625 in shrink
- Bend angles to dial 45
Checked against published worked examples from: Ugly's Electrical References (by name).
Details, formula, and sources
Formula or tableThree-point saddle: center bend = 2x the outer angle; outer marks at the field multiplier from center (2.5 x depth for the 45/22.5 preset, 2.0 x depth for 60/30) with the per-inch shrink rule (3/16 in per inch of depth for 45/22.5, 1/4 in for 60/30). Four-point saddle: two back-to-back offsets each = depth / sin(angle) separated by the obstruction width.
Source and editionStandard three- and four-point saddle-bend geometry taught in the electrical apprenticeship and Ugly's Electrical References, by name. NEC Article 358 governs the install.
Free accessFree read-only access to the NEC at nfpa.org/freeaccess. The saddle geometry is public first-principles math.
What governsEstimate. AHJ and licensed electrician govern. Verify against the NEC edition adopted in your jurisdiction.
API field namesmode, depth_in, preset, mark_spacing_in, shrink_in, center_bend_deg
- In-plane presets the 45/22.5 and 60/30 presets are the two that keep the conduit in-planemethod
- Shrink applied once the three-point shrink is applied once, not per outer bendmethod