3D Flattening

Sheet-Metal Design

General

  • The function flattens the model in the model window.
  • Flattening will take into account the strain of the sheet in accordance with the calculation method selected.
    • If the face to be flattened is a ruled face, flattening will not take into account the strain of the sheet.
  • 3D-flattening is necessary if, for reasons of manufacturing technology, the sheet is machined at the bends before the sheet is bent to its final shape.
    • When trimming a corner, flattening in the 3D model is necessary. Trim a Corner.
    • 3D-flattening is useful when positioning machined features, which are very difficult or impossible to model in a bent state.
  • Avoid unnecessary flattening and rebending of the model, as these may disrupt the model's geometry and make it unusable.
  • If the face to be flattened is a ruled face, rebending is not possible.
    • Ruler surfaces include conical surface and conical spline surfaces.
    • This means that you cannot add features (for example holes or forming features) to the flattened part and then rebend the part to the bent shape.
  • If the flattening of a ruled face fails, you can try to make the tolerance value larger.
  • Spline surfaces are flattened in relation to the so-called neutral axis starting from version 22.0.03.
    • The bends done with older versions are created in accordance with the selected surface.
    • If you want to update an old flatten drawing to a new one, the model's flatten configuration must be removed before updating the drawing.

Perform the flattening

  1. Select the ribbon bar function Sheet metal part | Tools | Unbend.
    • The program highlights the largest surface of the part as a reference surface, along which others will be turned.
    • The program prompts you to accept the surface or to click a new surface to flatten.
  2. Accept the selected surface or click a new surface.

    • Accept the surface suggested by the program by selecting Confirm. (Confirm = V key, middle mouse button or the context-sensitive function OK.
    • Or click a new reference surface.
    • The program opens the dialog box Bend Properties, if the stretch calculation method is
      • BendTable.*
      • K-Factor.
    • The program skips the dialog box Bend Properties, if another stretch calculation method is chosen, for example
      • DIN6935, FeAlCuZn, NEUTRAL, NOSTRETCH, etc.
  3. If the sheet metal part to be 3D-flattened is formed by a cylinder surface (ruler surface), accept the proposed end or select another end.
    • Accept the line suggested by the program by selecting Confirm. (Confirm = V key, middle mouse button or the context-sensitive function OK.
    • Or click a line at the stationary end.
  4. If you have selected BendTable or K-Factor as the stretch calculation method, fill in the data in the Bend Properties dialog box.
    • V-Opening. (If BendTable* is selected as the stretch calculation method.)
    • Tool Radius (if BendTable* is selected as the stretch calculation method).
    • K-Factor. (If K-Factor is selected as the stretch calculation method.)
    • You can assign values to all bends at once, or you can select a bend from the list and assign individual values to it.
  5. Select OK.

Create flattening based on the selected surface

  1. Select the surface parallel to which you want the other surfaces of the part to turn.
  2. Select the context-sensitive function Unbend.
    • Depending on the stretch calculation method, the program opens or skips the Bend Properties dialog box.
  3. Continue as above 3...4.

Note:
  • The strain calculation method is a sheet metal part property which you can redefine by clicking selecting the part and the context-sensitive function Properties.
  • If you make changes to the sheet, you can rebend it by selecting the function Rebend.
  • You can add a flattened view to a drawing by selecting flattening as one of the projections of the drawing. Create a Flattening Drawing
  • Every configuration of a sheet metal part can have its own flattening.