KEVOS® MAKEOS · Fabrication
Sheet Metal Bending Springback
How much will this bend spring back, and how far must it be overbent?
Final bend radius and angle after springback for sheet metal from the tool radius, thickness, yield strength and modulus, with the springback factor and overbend angle.
Open the calculatorRuns in your browser. No account needed.
How this tool works
Inputs, units and where to find them
| Input | Unit | Typical source |
|---|---|---|
| Bend radius before release (tool radius) | mm | Inside radius while the sheet is held in the tool. |
| Thickness | mm | Sheet thickness. |
| Yield strength | MPa | Yield strength of the sheet (higher strength springs back more). |
| Elastic modulus | GPa | Elastic modulus (steel 200, aluminium about 70 GPa). |
| Required final bend angle | ° | Bend angle required after release. |
Method and formulas
- x = Ri × YS ÷ (E t). Ri ÷ Rf = 4x³ − 3x + 1.
- Neutral length is unchanged: (Ri + t/2) θi = (Rf + t/2) θf; springback factor K = θf ÷ θi.
- Bend angle in the tool = required angle ÷ K.
- Example: 2 mm mild steel on a 6 mm radius: K = 0.99034, so bend to 90.878° for 90°.
Limitations
- Approximate formula for free bending; bottoming and coining reduce springback.
- Material property scatter makes trial bends essential.
- Example values are illustrations. Replace them with values for your actual task.
Typical uses
- Set overbend on a press brake
- Choose a punch radius for a final radius
- Compare materials for springback
Who it is for
- Fabrication supervisors
- Manufacturing engineers
- Estimators
What you get
- Final radius after springback
- Springback factor
- Angle to bend to (overbend)
Interpreting the result
- Large radius-to-thickness ratios and high-strength materials spring back most.
References
- Machinery’s Handbook, 29th edition (Industrial Press, 2012), printed pp. 1351–1352. Topic reference; no source tables or recommended settings are reproduced.
WORKOS tools are screening and decision-support utilities. Verify important financial, engineering, safety, legal or operational decisions using appropriate professional standards and your organisation’s approved data.
