I have an excellent German bending jig kit capable of making very complicated bends in wire and strip steel. However, it's complicated to set up and a bit of overkill for smaller jobs so I decided to build something a bit smaller and simpler to handle the occasional bending requirement on models and for various forms of shop tooling.
The first photo shows the component parts. The main part is the large cylindrical "table" (my term - there's probably a correct name but I don't know it). The table has a central hole surrounded by a spiral of holes. These holes accept 1/4" steel pins which acts as restraints and formers when bending. The central pin is also used to anchor larger dies (not shown) when bending larger radii. These dies are usually made up as required by the job at hand.
A 1/2" steel plate (still covered in red layout die) fits over the table and, constrained by three screws, is free to rotate about the table. It has a slot through which the bending "tooth" (more personal terminology) is attached. The slot allows the tooth to be adjusted in and out relative to the table center. This tooth is clamped such that the material to be bent is forced against the former as the plate is turned.
A delightfully crude handle made of 3/4" gas pipe attaches to the plate to provide plenty of leverage when bending.
Here another view of the table shows the groove into which the dog-pointed screws that anchor the plate to the table fit. The screws are sized such that, when tightened down, the plate is still free to turn.
Also shown is one of two flats on the table which are used when clamping it in the vise. They're a bit meek and need to be made bigger but I haven't gotten around to it yet.
And, finally, a picture of all the bits assembled and the bender mounted in the bench vise. A sample of the work that can be done is the small hook made of coat-hanger wire shown lying on the plate.
This thing is grossly over-built. My education is in physics, not mechanical engineering, so "design" is guided more by what stock is currently available that "for sure" won't break in the intended application. I'd wax apologetic but I surmise that I'm not the only one here who does this.
Regardless, this brute works well and, though heavy, shows no sign of bending or breaking.
