rebending

Rebending is the process of bending a previously formed workpiece again to achieve the desired final geometry. It is commonly applied in metal forming, including sheet metal, tubing, and piping, and can also appear in jewelry making and fabrication where precise bends are required after an initial bend.

The need for rebending arises from springback, manufacturing tolerances, design changes, or damage that occurred after the first bend. It may also be used to refine fit-up between parts or to correct skewed angles and radii.

In practice, rebending uses the same equipment as the initial bend: press brakes for sheet metal, tube benders for tubing, or hand tools with jigs, dies, and mandrels. Operators plan the final bend radius and angle, compensate for material springback, and may perform annealing or lubrication to ease deformation. Bends are typically added incrementally, with verification after each pass to avoid over-bending or distortion.

Material considerations include ductility, thickness, and heat treatment. More ductile metals tolerate rebending better, while work-hardened or brittle materials are at higher risk of cracking or surface damage. Some materials may require annealing between passes to restore ductility.

Quality control focuses on achieving the target angle and bend radius within specified tolerances, while monitoring for thinning, wrinkling, or distortions. Precise measurement and appropriate tooling are essential to minimize guide marks and ensure consistent results.