Nuovo modo di piegare le lamiere

[Frank S]

It's a good video, and maybe enough detail to duplicate one, step by step like the presentation, some portions are too high a viewing speed. More noticeable at the end, trying to see how bent parts look.

Can't visualize standing up deeper edges typical in box type forms by rolling; seems a lot deformation will occur in the un-clamped side.
Aside from reduction of material needed (compared to a big plate for an apron), I'm not recognizing a benefit in rolling to achieve shallow standard corners. What am I missing?

The single major advantage to rolling is the contact area while forming is miniscule compared to an apron & finger clamping break. allowing for lighter construction less bulk and easier to stow away in a small shop where space is always a premium, if a press break using punch and die set up then you need punches the same length as the inside of the box the same thing holds true for finger clamp apron folding breaks And even with a roller form you need something to fit between the 2 sides and tall enough to clamp the base material.
Now here is where a small sheet metal roller form can excel over an apron and finger or a press break for a press break for air bending the V width needs to be at least 5 times as wide as the metal thickness and the minimum flange width should be 6 times the material thickness. If we take for example 20ga takes 2.2 tons of force with a V width of 5/16", the minimum v width for 20 ga is 1/4" but it takes 2.9 tons of force. 18ga a common thickness for restoring old cars requires 5.4 tons with a 1/4" V while the recommended V for 18ga is 3/8" With a roller the force is greatly reduced to 100s of pounds force as opposed to tons, since you are only rolling a slight increase in the forming angle on each pass you need multiple passes through and the less of a bend angle you try to make on each successive pass reduces the possibility of deformation of the free edge of the flange. If you roll over a stiffening edge to the flange prior to making the box side, you reduce that even further. plus, it removes the sharp edge and may allow you to use lighter ga material.
I like his idea, since it is very similar in operation to a bead roller so far as the required strength of the machine is concerned, the major difference in unlike a bead roller the material remains stationary and the roll forming process is more akin to a multi station roll forming machine consider each pass as another rolling station.