Bending

Bending is the operation that plastically deforms a sheet of metal or a metal section along a straight line, imposing a precise angle without any removal or addition of material. The mechanical principle is controlled flexion: the workpiece is constrained on a V- or U-shaped die while a punch descends and forces the material past its elastic limit, producing permanent deformation. The subsequent elastic springback must be compensated by overbending by a few degrees.

The main machines are press brakes, available in mechanical, hydraulic and CNC versions. CNC press brakes manage complex bending sequences with automatic back gauges that position the workpiece to sub-millimetre precision, enabling the production of boxes, frames, brackets and metal fabrications of any geometry. In the maker and small-workshop context, manual bench folders and lever-operated sheet-metal brakes cover thicknesses up to 1.5–2.5 mm on aluminium and mild steel, proving indispensable for building enclosures, mounting brackets and custom components.