I manufactured a more practical and universal do-it-yourself bender. What you can see on the photos is the main base-plate with some side-straightenings and bending axes of different diameters. The location of the bearing-roll can be changed on the handle bar in a V-shape form, depending on the bending radius and the thickness of the material. The side-straightening screws have an important roll, otherwise, the radius performed doesn't have a nice, smooth arc shape. If you need to do a more complex form, you can use more vertical axes, and side-straightenings, this you can see on the example with a triangle between the photos.
This rod end squarebar bender has 3 kinds of changable rolls with a diameter of 50,70,90mm, so we can do 3 different curve bends. Our job is also easyer with the 2 prolongable powerbar.
In this case the task was to manufacture hooks from roundbar with a diameter of 8mm, in two lenght. After many trials I managed to make a fixing point at the corner of the slot, and the bending is made from one root (close to the bending point)by a bearing roll with the help of a power-handlebar. The second phase is the breaking of the hookstem so that the already hanged hook should stand vertically to the hanging point. The breaking of the 2 types of lenght is ensured by 2 types drilled powerbars. This process was a challengingly kind and visual one.
We got an order for a bender that can bend 8 and 10 mm diameter stainless-steel rod. It's working easy, and you can make bends on a round bar in all 3 dimension, as you can see on the photos.