Sheet metal
Check if inner radius is too small. Min Ri depends on material and thickness: 0.5×s (mild steel), 1×s (stainless), 1–2×s by thickness band (aluminium, soft 5052-H32 temper assumed; 2–3×s for a declared 6xxx T5/T6 temper such as 6061-T6). Flags radii below 90 % of the limit. Hems are skipped.
Cold bending of flat rolled steel
Sheet metal · CC0-1.0
Model example
Inspect the inside corner: radius 4 mm in 2 mm sheet, with two tangent flanges. The smooth generous corner is the control.
Dimensions (approx.): 46 × 46 × 60 mm
Compare: 90° bend: R0.3 / t3
Sheet metal · CC0-1.0
Model example
Inspect the inside corner: radius 0.3 mm in 3 mm sheet, with two tangent flanges. The almost sharp fold is the intended issue.
Dimensions (approx.): 43.3 × 43.3 × 60 mm
PRU-002: expect an inside-radius heuristic warning: 0.3 mm against a recommended minimum of 1.5 mm (0.5 × thickness for mild steel up to 4 mm; related DIN 6935 guidance, not a normative radius table).
Finding expected