Bent tubing is key. Roll cages need it. Tube frame chassis need it. Even the storage arrangement for my welding clamps needed it. There are a number of ways to go about bending tubing. Rotary draw benders like the Hossfeld Universal bender make a tight bend at one point. Three-roll benders create more gradual curves. But none of them compare to this automated CNC tube bender that just spits out steel in any shape you want. I could watch it all day.
Information on this Nissin bender is a bit sparse, but I’ve come across these two videos of it’s impressive capabilities. Tube to be bent is supported, lubricated, and driven forward at a constant speed by the stationary part of the machine. As the tube is pushed through the machine, it is forced through the moveable die, which positions itself appropriately to bend the tube as needed.
The bend is originally specified in terms of the geometry of the desired part. That bend geometry is translated into a set of instructions that control the position of the moveable die. The die will be positioned in the right place at the right time such that the tube is bent the right amount and in the right direction to produce a finished piece closely matching the original specifications.