Die Bending

Die bending presses a sheet between a matching punch and die to form a precise bend angle.

Die Bending uses a press brake with shaped tool sets (punch and die) to bend sheet metal along defined bend lines. It is typically the second operation after Sheet Cutting, forming the flat cut piece into the final 3D shape.

Die Bending is an automatic workstep — it runs automatically after Sheet Cutting completes on a sheet metal part. You do not click a button to run it; WSi creates the Die Bending node as part of the import or creation workflow.

When to use this process

Die Bending is available automatically after Sheet Cutting when:

• You have imported a sheet metal part (DXF, GEO)
• The part requires bent flanges, channels, or other folded features
• The design specifies bend angles and radii

Editing Die Bending Parameters

Edit die choice

The die selection dialog lets you view and override the tools chosen for each bend. Open it by right-clicking a Die Bending node in the Graph View and choosing Edit Bending Tools.

WSi automatically selects the tool pair based on sheet thickness, material, and target bend angle. If the geometry requires a combination not in the list, WSi flags a die choice failure on that bend.

Edit flip side usage

Right-click the node and select Edit Flip Side Usage to specify whether the part is flipped before or after the bending operation. Flipping affects which side of the sheet contacts the die and is important for symmetrical parts or parts with asymmetric flanges.

Edit bend correction

Right-click and select Edit Bend Correction to manually adjust the bend deduction or compensation values. Bend correction compensates for springback — the tendency of the material to partially return to its original shape after the bend is released.

TIP

Bend correction overrides are flagged with an orange warning indicator in the Graph View. This helps you track where you have deviated from the database defaults.

Result

After Die Bending runs:

• A Die Bending node appears in the Graph View, connected from the Sheet Cutting node
• The Tree View shows bend results: bend angles, radii, and any warnings
• The 3D shape of the bent part becomes available as output
• If the geometry could not be bent (die selection failed for some bends), WSi shows an error with the affected bends highlighted

WARNING

If bend geometry is inconsistent with the sheet cutting geometry (e.g., a bend line falls on material that was cut away), WSi shows a warning. Check the geometry in the Graph View to locate the issue.

See Also

• Laser Sheet Cutting — the cutting operation that precedes bending
• Sheet Metal Folding — an alternative bending method

Parameters

The parameters for this process are configured in the database — see the Sheet Bending page.

Technical Background

A press brake is a large hydraulic or mechanical bending machine that consists of a bed (the bottom structure) and a ram (the moving top beam). The upper tool, called the punch, is mounted on the ram; the lower tool, called the die, sits in the bed. Together they form the die set used for each bend.

The sheet metal is placed over the die opening on the bed. The ram descends and forces the material into the die cavity, creating the bend. The inside bend radius is determined primarily by the punch nose radius — it will be approximately equal to it, with some variation due to springback.

The die opening width (V-width) determines both the achievable bend angle and the force required. A wider die opening produces a gentler bend but requires more tonnage. Conversely, a narrower die gives a sharper radius but demands higher force.

Springback is a natural phenomenon: after the punch releases, the material partially returns toward its original flat shape. The amount of springback depends on the material's yield strength, modulus of elasticity, thickness, and the bend geometry. WSi calculates the overbend compensation needed to achieve the target angle after springback occurs.

Multiple hits — such as coining or ribbing — can progressively increase the bend angle beyond what a single hit achieves, which is useful for tight angles or materials with high springback. Bend direction is controlled by which side of the punch contacts the material, determining whether the flange bends upward or downward.