Scale objects around a rotational pivot

Scale an object with respect to a rotation point and axis of deformation.

Modify the rotational scale

Select Transform > Modify > Rotational Scale or click its icon.
You can pick and unpick geometry in the Object Lister by clicking the DAG nodes.
The system prompts you to enter the first pivot point.
Define the pivot point for the deformation by typing an X, Y, Z location or by using the mouse. A cross-hair, the pivot point, appears to mark the center of the rotational scale.

Note
The system calculates the best fit for the model according to the deformation values you request. For the most accurate fit, enter values using the keyboard rather than the mouse.
The system prompts you to enter another pivot point. The two pivot points define the axis for deformation.
The geometry deforms about the pivot point and toward or away from this second point.

Define the second point by typing an X, Y, Z location, or using the mouse. Another cross-hair appears. The selected curves and surfaces rotate around this axis point.
If no objects are picked, the system prompts you to select geometry.
If you hold down Shift, you can select several objects. You can continue selecting and deselecting geometry during the function.
The system tells you the current scale and prompts you to adjust the scale factor.
Select more objects by holding down and clicking with the .
Type a new scale value or use the to adjust the scale by moving the object.
This new value can be a new scale or a new number of divisions, depending upon the Type of input mode that you chose in the Rotate Options window.

Example

To create an eight-spoked wheel by rotationally scaling a spoke of a five-spoked wheel:

Select the geometry for one of the spokes, and toggle the rest of the model invisible or templated, or delete it. (You can use intersecting planes to "slice" out a section of the wheel.)
Select Transform > Modify > Rotational Scale ❒ or double-click its icon in the tool palette.
In the option box, set the input mode to Number of divisions.
Place the pivot point at the center of the wheel and the second point along the spoke to set the axis of rotation.
Now enter how many divisions were in the original model. (Type 5 for this example.)
Enter the new number of divisions. (For this example, type in 8.) The element is scaled to its new angle.
You are now finished deforming the model. To complete the new wheel, create seven additional copies of this spoke, each rotated by the correct amount.
To make these copies, use Edit > Duplicate > Object. In this example, the wheel was in the X - Z plane, so the rotation is about the Y axis. Set the following options in the Duplicate Object Options window:
- Rotation – Y 45
- Number of duplicates – 7
- Geometry type – instance
A new wheel is created, with eight spokes:

To transform objects with construction history

Some functions, such as Surfaces > Revolve create an object that has construction history. The construction history of an object that is being transformed cannot be maintained.

A confirmation box appears, asking if you wish to continue even though the construction history will be removed:

If you select YES, the construction history is deleted and you can proceed with the operation.
If you select NO, the operation is canceled and the construction history is kept.

Select Undo at any time to reset the geometry to its original values (without construction history).

Any continuity present in the model is lost by this deformation and you will have to rebuild the surface. If you keep the deformations relatively small, the resulting continuity may work for presentation only.

Note

Construction history enables curves or surfaces to adjust to changes in the geometry of the objects that generate them. If construction history is lost, to update the generated objects you must re-create them.

For more information about construction history, see Construction history.