Hi everybody.

Using Flow as an unfold tool is theoretical brilliant. As long as you need no close tolerances for practical produktion.
The "newtral" line is not allways in the middle between the outlines. During the bending process the outside material will
be stretched and the inside material comes under kompression. That means the layer of the inside will be thicker and at the outside thinner; and the newtral line changed allways it's position depending of the relation between bending radius and the
thickness of the material.

For this universitys made a lot of testlines to find a formula for a factor you can use for the rigth unfolded length of
bending bows. For every combination of thickness and inside radius you will have a special K-number.

Example: Inner bending radius = thicknes of the sheet; K-number =0,365
Inner bending radius = 2 x " " ; K-number =0,400
Interpolation is possible.

This exaple works with normal sheets up 5 mm thicknes.
To work with sheets need a lot of expiriences and allways testbendings.

Good luck...... and have fun.
Hans

next time I send a formula