It's easy to bend di-arco precision bending machines
by Di-arco
copyright© 1968
Soft cover
Here is the current owners site along with a current version of this booklet
http://www.diacro.com/catalogs.html
A give away that covers bending on the Di-Arco type benders. From simple eye bending, whether centered or off-centered, circle,zero radius,scroll,square,spring and coil,loop and spiral, tube by roller or tube by follow block,Special set ups,edgewise bending,channel flanges in or out,angle flanges in or out,special shaped or wide materials.
Along with other information you need about the complete line of benders and accessories.
The PDF downloadadable one covers about the same stuff only you don't have to hunt for a copy to get.
Their other company is Acrotech Inc. which deals in urethane material and rollers along with sheet rolling machines. All the catalogs are on the download page.