Estimate the preliminary overbend required to compensate for springback and achieve a target finished angle.
Bend Inputs
The measured finished angle from an actual test bend is the most useful input for machine-specific springback compensation. The material and geometry fields provide additional reference information.
Ready to calculate preliminary springback compensation.
Springback Result
Recommended Forming Angle
—
Springback
—
angle recovery
Overbend Required
—
from target
Measured Error
—
measured − target
V / Thickness
—
tooling ratio
Strength / Thickness
—
reference
Springback Analysis
Measured Test Bend
Target finished angle—
Formed/programmed angle—
Measured finished angle—
Angle error—
Observed springback—
Compensation
Required overbend—
Recommended forming angle—
Material—
Yield strength—
Inside radius—
Springback Compensation Table
Parameter
Value
Interpretation
Compensation Effect
Springback Diagram
Simplified springback concept
Overbend → target angle after springback
The illustration is a simplified forming concept and is not a machine, tooling or dimensional drawing.
Measured Springback Formula
When a test bend is available, the observed springback can be estimated from the angle imposed during forming and the final measured angle.
Observed Springback = Measured Finished Angle − Formed Angle
For example, if a part is formed to 86° and relaxes to 94°, the observed angular recovery is 8°. The sign and direction depend on how the bend angle is defined.
Overbend Required for a Target
For a test-bend-based correction, the measured finished angle provides a direct indication of how much the process is moving away from the desired target.
For the common case where springback makes a 90° bend open to a larger angle, the forming angle should be reduced by approximately the measured angular error.
Springback is influenced by material strength, thickness, bend radius, die opening, tooling geometry and the forming method.
Higher-strength materials generally exhibit greater elastic recovery.
Thinner material can respond differently from thicker material under the same tooling conditions.
A larger inside bend radius can affect the amount of springback.
Die opening and punch geometry influence the bending condition.
Air bending, bottoming and coining have different springback behavior.
Material batch and temper variations can change the actual result.
Using the Tool for Production Setup
For repeat production, use a test piece made from the same material and thickness with the same punch, die and machine setup.
Enter the desired finished angle.
Enter the actual measured finished angle from the test bend.
Enter the angle used during forming.
Calculate the observed springback and required overbend.
Apply the recommended forming angle.
Make another test bend and measure the finished angle.
Update the compensation using the latest verified measurement.
Important Limitations
This is a preliminary sheet-metal springback compensation tool.
It does not perform a full elastic-plastic bending simulation.
It does not predict exact springback from material properties alone.
Actual springback depends on the specific machine, tooling and material.
Yield strength varies by material grade, temper and batch.
Grain direction can influence bending behavior.
Tool wear and machine calibration can affect the finished angle.
Angle measurement accuracy affects the calculated compensation.
Air bending, bottoming and coining should not use identical compensation assumptions.
The recommended angle should be verified using a physical test bend before production.
Important: Use the result as a preliminary process-setting reference. Verify the actual springback and compensation with test bends, accurate angle measurement and the machine/tooling manufacturer's procedures.
Frequently Asked Questions
What does the Sheet Metal Springback Compensation Tool calculate?
It estimates the preliminary overbend required to compensate for observed springback and achieve a target finished angle.
What is springback?
Springback is the elastic recovery of the sheet after forming pressure is released, causing the finished bend angle to change.
How much should I overbend?
A practical starting point can be obtained from the measured difference between the target finished angle and the actual finished angle from a test bend.
Does stronger material have more springback?
Generally, higher-strength materials tend to exhibit greater elastic recovery, although the actual amount depends on the complete bending setup.
Does the die opening affect springback?
Yes. Die opening and tooling geometry affect the bending condition and therefore can influence the resulting springback.
Is the calculated compensation exact?
No. It is a preliminary estimate. The actual result should be verified with a test bend using the production machine, tooling and material.