.svg)
Neutral Axis
The theoretical plane within the material cross-section that neither compresses nor elongates during bending. The neutral axis location determines accurate flat pattern calculations; it shifts toward the inside of the bend, closer to the compression side.
The neutral axis is an imaginary plane within the material thickness that neither stretches nor compresses during bending, material on the outside of the bend stretches (tension) while material on the inside compresses. Its location shifts inward as the bend becomes tighter relative to the material thickness, which is why the K-factor (the ratio of neutral axis position to material thickness) varies with bend conditions.
Understanding the neutral axis is essential for calculating accurate bend allowance and bend deduction values, which in turn determine the correct flat blank size before press brake forming. If the neutral axis position is assumed incorrectly, the flat pattern will be the wrong size and the finished part dimensions will be off, a particularly expensive mistake on multi-bend parts with tight tolerances.
This is why experienced fabricators develop material-specific bend tables based on actual measurements rather than relying solely on theoretical calculations.
Price Your Project
Receive a free, custom quote for you project. Midwest Metal Fabrications can handle any job, small or large and is ISO 9001:2015 and AS9100 Certified.