Sheet Metal Bend Allowance

Bend allowance and flat blank length from K-factor and angle.

Run the calculator

Formula and source

BA = (π / 180) × angle × (R + K × t) where K is the K-factor (neutral-axis offset) and t is sheet thickness; flat blank = leg1 + leg2 + BA - setback.

Machinery's Handbook by name; SME Sheet Metal Forming by name.

Audience

This tile is built for carpentry and the adjacent professions in the Carpentry and Construction group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.

Related tools

Posture

Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.