Fine Blanking

Fine Blanking Machine

Conventional vs fine blanking

Assorted mechanical parts made by fine blanking

Fine blanking is a shearing process that produces parts with a higher quality edge than conventional blanking. In fine blanking pressure is applied to both sides of the part during the shearing action. The image shows a part made by conventional blanking (top) and fine blanking (bottom).

Fine blanking holds tight dimensional control through the entire thickness of the part. Additionally tight flatness specifications can be achieved without secondary grinding. Fine blanking can produce almost any 2D shape including those with holes and cutouts. Examples of parts made by fine blanking include gears, jewelry, money clips, parts for watches and clocks, decorative items, etc. Fine blanking can shear most types of sheet metal, however tool life decreases with material hardness. The process requires a custom steel punch and die tool in the shape of the final part.

Fine Blanking Design Considerations

• Rounded corners are preferable to sharp corners.
• Holes and cutouts add to cost.
• Avoid shapes with features smaller than material thickness.