Here is a AI sumary of the meaning of K-factor when rolling plates (And for all those out there with a better answer, please dont hate, just add better answer/description to the conversation, thank you):
When you bend or roll a metal plate, the material on the inside of the bend compresses, while the material on the outside stretches. Somewhere between these two surfaces lies a magical line that doesn't change length at all: the neutral axis.
The K-factor is the ratio that determines exactly where this neutral axis sits, and it is absolutely critical for calculating how much a plate will "stretch" during the rolling or bending process.
The K-factor is defined by a simple ratio: K=t/T (t over T, not divided.)
t = The distance from the inside surface of the bend to the neutral axis.
T= The total thickness of the plate.
Because it's a ratio of the material's thickness, the K-factor is always a value between 0 and 1. In a perfect, theoretical world where materials don't stretch or compress differently, the neutral axis would be dead center ($K = 0.5$). In reality, because metal compresses less easily than it stretches, the neutral axis shifts toward the inside of the bend, meaning K-factors usually fall between 0.3 and 0.5.
Why It Matters When Rolling Plates
When you roll a flat plate into a cylinder or a curve, you need to know exactly how long the flat sheet needs to be before it hits the rollers. If you don't account for the K-factor, your final part will either be too big or too small.
Calculating Flat Length (Developments): Engineers use the K-factor to calculate the Bend Allowance—the actual length of the material along the neutral axis.
-Precision Manufacturing: If you are rolling heavy plates for pressure vessels, pipes, or tanks, even a tiny error in the K-factor can result in a cylinder that doesn't close properly or violates strict structural tolerances.
Typical K-Factor Values
The exact K-factor changes depending on the material type, its hardness, the thickness of the plate, and the radius of the bend. However, here are some common industry starting points:
-Soft Copper / Brass 0.35 – 0.40
-Aluminum (Soft/Medium) 0.40 – 0.45
-Medium Carbon Steel 0.40 – 0.45
Maybe this is way of what you ment for FredoBend, but it sure would be nice to have. And the features you allready added, like editing the original plate, and then go back to rolled, is great.
