Felling Notch and Hinge Geometry
Recommended open-face notch depth, hinge thickness, and hinge width from the felling-cut diameter.
Example
You enter
- Diameter at the felling cut (in) 20
- Notch depth (% of diameter) 22
- Open-face angle target (deg) 70
You get
- Notch depth 4.4 in
- Hinge thickness 2 in
- Hinge width 16 in
Details, formula, and sources
Recommended open-face notch depth, hinge thickness, and hinge width from the felling-cut diameter, with the ANSI Z133 cautions. A qualified faller governs.
notch_depth = dia x notch_pct/100 (default 22%); hinge_thick = dia x 0.10; hinge_width = dia x 0.80; open-face angle 70 deg or more.
ANSI Z133-2017 (Arboricultural Operations - Safety Requirements) open-face felling practice by name; standard faller guidance.
ANSI Z133-2017 is a published consensus standard. The open-face geometry is standard faller practice.
Math aid for personal verification. Stop work and consult the qualified person on site if any number does not match the field condition.
Field names used by the API: cut_dia_in, notch_pct, open_face, notch_depth_in, hinge_thick_in, hinge_width_in
- Open-face defaults notch 20-25% of dia (default 22), hinge ~10%, width ~80%, open face 70 deg+ANSI Z133-2017 / faller practice