A calculation you can follow.

The single-bend model.

Lengths are converted to millimeters internally using exactly 25.4 millimeters per inch. A is the amount bent; the included angle is θ = 180° − A. Inputs retain precision when you change the display unit or angle convention.

The current numerical support is T > 0, R > 0 and 1° ≤ A ≤ 175°. Zero-radius bends, flat stock as a bend and closed hems are outside this implementation. K must be within 0–1; this is a mathematical bound, not a recommended process range.

Measured values and L profiles.

A measured BA is used directly. A measured BD gives BA = 2 × OSSB − BD. The implied K is checked for consistency with the supplied geometry; conflicting values are not averaged or silently corrected.

For an L profile, each outside mold-line dimension extends to the virtual sharp. Subtract OSSB to obtain each straight section; both must remain positive. Flat length is the two straight sections plus BA. The tool supports a constant-width, constant-thickness open strip with one bend.

Gauge table provenance.

The reference contains only rows listed by Metal Supermarkets for the four supported materials. Source inch values are retained, and metric values are calculated from them. No wire-gauge formula, interpolation or assumed coating weight is used to fill gaps.

UniPunch provides a separate cross-reference for three materials. Its four-decimal values can differ from the selected source’s five-decimal display by up to 0.00005 in. We retain the selected source instead of averaging. Gauge values are nominal; actual thickness must be measured for bending.

Check the result against your process.

The formulas describe idealized bend geometry. Material, tooling and process settings affect the finished part. Check the calculated flat length against a measured test bend made under the same conditions before using it for production.

The calculators do not predict springback, required press force, tooling access, collisions or cracking, and do not generate machine programs. Multi-bend profiles and closed hems are outside their scope.

Source register.

Calculation records.

Copied and printed records include inputs, method, results, source notes and model version. Local saves are explicit and remain in your browser. A record from an incompatible model is not automatically recomputed or overwritten.