BIM Sections

Command: BimSection

Overview: In this lesson, you learn how to create and manage plan, elevation and section planes. Creating design documentation out of these section planes will be covered in a future lesson.

Lesson Objectives

After completing this lesson, you will be able to:

• Cut through a BIM model horizontally to show the details on a floor plan.
• Cut through a BIM model vertically to show the interior detail.
• Display a BIM model with a vertical section outside the model.
• Toggle the Clip Display property of a BIM section entity.
• Control the visibility of your BIM section cuts.  

Define Section 

In BricsCAD BIM, the Define Section tool allows you to create BIM section entities. The BIM section allows you to section a BIM model by a plane and thus view the interior details.

Menubar: BIM > Define Section
Toolbar: BIM > Define Section
Quad: Model tab > Define Section
Keyboard: BIMSECTION

When defining a BIM section, the section tracker is attached to the cursor.

The following illustration shows the BIM Section Tracker elements such as Section plane (1) and View direction (2).

The section plane lies in the XY-plane of the current coordinate system (WCS or UCS). The view direction (2) is in the negative direction of the current coordinate system.

Note:

• If Dynamic UCS (DUCS) is ON, the section plane aligns to the face of the 3D solid under the cursor. Hit the TAB-key to select an obscured face.
• You can press the Shift-key to lock highlighted plane, allowing you to specify the definition point for the BIM section entity outside the face of the solid.
• The section line is parallel to the X-axis of the coordinate system (WCS, UCS or DUCS).

Procedure: General steps to create a BIM Section

1. Select Define Section from the No Selection Quad.
   You are prompted: Select a point to place section or [Detail/Interior/Scale/Reflected ceiling]:
2. Do one of the following: 

• To create a plan section, click a point anywhere outside the model.
• Hover the cursor over the face of a 3D solid which is parallel to the section plane you want to create. The section tracker aligns to the face under the cursor, on the condition that DUCS is active. Left-click.
• Optionally, hit the Shift key to lock the highlighted plane, allowing you to start from a point outside the selected 3D solid face. Next, left-click.

The initial section plane displays dynamically and the 3D model is clipped accordingly.

3. You are prompted: Specify distance:
   Do one of the following:
• Type a value in the dynamic dimension field to offset the section from the initial position.
• Left-click when the section plane is at the location you want it to be.

The BIM Section entity is defined.
The Section Type will depend on the section plane directions and its place in the model.
The following illustration shows the BIM section types on the 3D entity.

Procedure: Defining a plan section

Note: A plan section is best defined in the WCS ( World Coordinate System).

1. Select the Define Section tool from the Quad.
   You are prompted: Select a point to place section or [Detail/Interior/Scale/Reflected ceiling]:

2. Place the Section Tracker near the 3D model and click.
   
   
   
   The initial section plane lies in the XY-plane (Z = 0) of the current coordinate system (e.g. the WCS).
   The section plane displays dynamically and the 3D model is clipped accordingly.
   
   

3. You are prompted: Specify distance:
   If Dynamic Dimension is ON, the current distance displays in a dynamic dimension field.
   Do one of the following:
• Move the cursor and click when the section plane is at the desired height.
• Use an Entity Snap to specify a point.
• Type a value to define the offset from the initial position of the section plane.

The plan section is defined.

Procedure: Defining a cross section 

Note: Make sure Dynamic UCS (DUCS) is enabled when defining a cross-section.

1. Select the Define Section tool from the Quad.
   You are prompted: Select a point to place section or [Detail/Interior/Scale/Reflected ceiling]:
2. Place the section tracker over a 3D solid face (8) which is parallel to the cross-section to be defined.
   
   
   Click when the face highlights and move the section tracker inside the 3D model.
3. The section plane displays dynamically and the 3D model is clipped accordingly.
   
   You are prompted: Specify distance:
   If Dynamic Dimension is ON, the current distance displays in a dynamic dimension field.
4. Click when the section plane is at the desired location or specify a distance.
   The cross-section is defined.
5. (Optional) Drag the Start grip to move the section plane.

• Drag the End grip to rotate the section.
• Click the Arrow grip to flip the view direction.

Procedure: Defining an elevation

Note: Make sure Dynamic UCS (DUCS) is enabled when defining an elevation.

1. Select the Define Section tool from the Quad.
   You are prompted: Select a point to place section or [Detail/Interior/Scale/Reflected ceiling]:
2. Place the Section Tracker over a 3D solid face (10) which is parallel to the elevation to be defined and click when face highlights.
   
   
   You are prompted: Specify distance:

3. Move the section tracker outside the 3D model and click to define the elevation.
   The elevation is defined (11).

Vertical sections outside the model (no geometry is sectioned) get the Elevation section type automatically.

Note that elevations are used to create design documentation. This is a topic that will be covered in future lessons.

Procedure: Changing the default properties of an existing BIM Section 

The default properties of a BIM section entity are based on the .dwg file of ‘Section Settings’ drawing in the BIM/Sections subfolder of the Support folder.

1. Select an existing BIM section in the drawing.
   The current properties display in the Properties Bar.
2. Define the properties of the BIM section entity.
   The following illustration shows the Properties bar with the current properties of a BIM section.
   
   

Section Entity:

Geometry:

BIM:

The following illustration shows the BIM section callout positions e.g. start (12), mid (13), end (14), and start-end (15).

Click the green arrow () to flip the view direction of the section.

Procedure: Toggle the clipped display property of a BIM section entity 

The Clip Display property of the BIM section allows to temporarily clip 3D models. The Clip Display status allows to progress using all modeling and editing operations on all drawing content.

1. Create a section view in your drawing.
   The following illustration shows the 3D model of a villa with a plan section (16) for the ground floor plan.

2. To clip the 3D model, do one of the following:
• Double click the section entity.
• Select Clip Display from the Quad.
• Select the section plane and set the Clip Display property to Yes.

Note: The Clip Display can be on for multiple section entities simultaneously.

In the following illustration, the Clip Display is turned ON for two BIM section entities (17,18). These section entities are in opposite view directions: section plane 18 is a plan section, section plane 17 is a reflected ceiling section.

Optionally, the State property for the current section can be changed from Plane to Volume in the properties panel.

In the following illustration, the clipped section is shown in the Volume state (19).