Definition
Bending is a sheet metal forming process where a flat blank is plastically deformed along a straight line, typically using a press brake with a punch and die, to create an angled or folded shape. Unlike machining, no material is removed; the part's flat pattern is designed to account for material stretch at the bend.
Why bend count and sequence matter for cost
Each bend typically adds its own setup and cycle time, and the order of bends matters: a part with several bends in different directions may need reorientation between them, which is why bend count and sequence, not just the final shape, drive cost.
Where it appears on the drawing
As a bend line and angle on a flat pattern or folded 3D model, often with a specified bend radius and, for precision work, a tolerance on the resulting angle.
Common mistakes
Designing a flat pattern without accounting for material stretch at the bend (bend allowance), which can leave a folded part's final dimensions off from what was intended.
Each bend typically adds its own setup and cycle time, and the order of bends matters: a part with several bends in different directions may need reorientation between them, which is why bend count and sequence, not just the final shape, drive cost.
See how Blake reviews a partFrequently asked questions
Does bending remove material?
No, it plastically deforms the material along a line; the total flat-pattern area accounts for stretch at the bend rather than being reduced.
Why does bend order matter?
Because a part with bends in different directions may need to be reoriented in the press brake between bends, and some bends can make later ones physically harder to reach.
What is bend allowance?
The extra length added to a flat pattern's dimensions to account for material stretching as it's bent, so the final folded part comes out at the intended size.