Many Autodesk Revit families need to have a portion of the family be able to rotate depending on parameters in the family. A door swing is the most common example of this, as most Revit Architecture users want to be able to specify the swing angle of the door panel. It seems that getting rotation angles to work correctly is something that is battled by many family creators, so in this article, I’ll give you the keys to getting that rotation angle to work correctly. This technique can be used on door swings and other items that need controlled by a rotation parameter within the family.
When creating a rotation angle, the first key is to use a Reference Line instead of a Reference Plane. The other key is to lock the Reference Line endpoint to the intersection of two Reference Planes that represent the rotation point of the rotating item. Many users have difficulties because they fail to do both of these key steps.
Let’s take a look at the steps to accomplish the 2 keys just mentioned above.
- Start a family using the appropriate template.
- While the Revit family template that will be used to create your specific family will vary depending on the family requirements, I will use the Generic Model.rft template for this illustration. (The information shown in this illustration is applicable to other family templates, but the Generic Model.rft template provides me with a clean template to illustrate the rotation topic.)
- Draw the Reference Line.
- Align and lock the endpoint of the Reference Line to the Reference Planes.
- From the Modify tab, and the Modify panel, select the Align command.
- Select the vertical Reference Plane.
- Select the endpoint of the Reference Line. After moving the cursor over the endpoint of the Reference Line, you may need to press the TAB key a few times to cycle through available options until you see the dot appear at the endpoint. The dot represents the endpoint and is the 2nd key to getting the rotation to work correctly.
- Select the Lock button that appears after aligning the endpoint. This will actually lock the endpoint to the vertical Reference Plane.
- After locking the Reference Line endpoint to the vertical Reference Plane, repeat the same process to lock the same Reference Line endpoint to the horizontal Reference Plane.
- Locking the single Reference Line endpoint to BOTH Reference Planes ensures that the intersection will be the rotation base point for the Reference Line.
- Create a Rotation Angle parameter that will adjust the Reference Line to the desired angle.
- From the Annotate tab, and the Dimension panel, select the Angular command.
- Place the dimension by picking the Reference Line and the desired Reference Plane.
- The actual Reference Plane that is selected is very important, as this will dictate the angle that is specified by the user in the parameter that will be created in the next step. Choose the reference plane that will make sense to the final user when they specify an angle in the future.
- Highlight the angular dimension. Go to the Options Bar (typically at the top of the screen), and select <Add parameter…> from the Label option.
- In the Parameter Properties dialog box, type “Rotation Angle” in the Name box. (This can be any name that you desire, such as Swing Angle for a door. Just make sure that you maintain consistency with names.) Select the Instance option if you desire the angle to vary for each instance occurrence of the family inside a project. Pick the OK button to exit the dialog box.
- Flex the geometry to make sure that the Reference Line rotates as desired.
- Press the Modify button to make sure that nothing is selected.
- Go to the Modify tab, then the Properties panel, and select the Family Types button.
- Next to the Rotation Angle parameter, type in a new value and pick the Apply button.
- Verify that the Reference Line rotates as desired. Pick the OK button when you are satisfied that it rotates as desired.
After going through the above steps, you can create and lock actual geometry to this Reference Line, such as Extrusions, Model Lines, Symbolic Lines, Components, etc. Be sure and lock down all of the dimensions for the items that you create to ensure that they move with the Reference Line and still maintain their required size and shape.
Whether you are creating a door panel or something else, using the above steps will allow that item to rotate around a specific base point.
The above steps were performed in Revit Architecture 2011, but are similar in Revit Structure and Revit MEP. If using earlier releases, the same process can be utilized, but the command buttons may be in different locations in the interface.