90° Bend Flat Pattern Calculator
Calculate flat pattern blank development length for sheet metal bent at 90° angles.
Choose profile type:
- Angle
- Channel
- Zigzag
- G-profile
- C-profile
Enter material thickness S and bend radius R from the dropdown lists, then enter flange dimensions A, B, C, D, E. Click Calculate.
Thickness S:
mm
Radius R:
mmCalculation Formula
Flat pattern blank development length is calculated as:
L = L₁ + L₂ + ... + Lₙ + n · Lᵢ
where L₁, L₂...Lₙ are straight flange section lengths, n is the number of bends, and Lᵢ is the bend allowance length:
Lᵢ = (π / 2) · (R + x · S)
where x is the neutral axis shift factor (K-factor based), selected according to the R / S ratio.