Boolean Operations - Adding and Cutting Solids

Adding solids together and using one solid to cut volume from another are called Boolean operation. These operations can be performed when solids have volume in common (overlap) or have at least one common (or partially common) surface. In addition to Boolean operations described in this section, there are other predefined Boolean operations including drilling holes, milling, creating grooves, filleting and chamfering.


Boolean Operations

Add Solid – ADD, Ctrl + A

Combines two solids into one object. First select the solid to be added, then select the solid to be added to. Although the final result is the same, the selection order can be important. If the solids have properties such as certain attributes or group membership, the final solid will have the properties of the second selected solid - the root solid.

Cut, Delete Cutting Solid – CUT, Ctrl + W

Uses one solid as a cutting tool to remove volume from another solid. The cutting solid is then deleted. For example, to create a conical hole, use a cone as a cutting tool to remove volume from a cube.

Example of Cut, Delete Cutting Solid. The spline is the cutting tool, the pin is the root solid.


The spline is embedded into the pin.


The resulting cut solid. The spline is deleted.


Cut, Keep Cutting Solid - CUTS

Similar to Cut, Delete Cutting Solid, except that the cutting solid is not deleted.

Selective Add - ADDPC

Similar to Add, used to add solids that overlap or extend past the root solid. Select the added solid at the section you want to remain; other sections will be trimmed.


Example of Selective Add. The cylindrical pin is to be added to the U-iron. The pin is selected where indicated.


The resulting added solid. Only the section selected was added, the rest of the solid was trimmed.


Using the same initial solids, the pin is selected at a different location.


The resulting added solid. The middle section only was added.


Selective Cut, Delete Cutting Solid - CUTPS

Similar to Cut, Delete Cutting Solid. For the cut solid, only the section you select will remain; other sections will be deleted. The cutting solid is also deleted.

Selective Cut, Keep Cutting Solid - CPSS

Similar to Selective Cut, Delete Cutting Solid, but the cutting solid is not deleted.

Solid Intersection - SIN

The result of the solid intersection is a volume common for both selected solids.


Common Boolean Operations

Hole, Mill, and Groove all use a cutting tool to remove volume. The dimensions of the cuttings tools are specified as for basic 3D elements; you can also copy dimensions from another object. For example, in the Hole function, you can copy the dimensions of an existing hole.


Holes, Grooves, Cutting by Planes

Hole - HOL

Remove cylinders (holes) from objects. You can optionally create recesses, or use a chamfered or tapered bottom.



Hole creation window


Mill - MILL

Removes volume by using a box as the cutting tool. If the box dimensions are large enough, you can, in effect, cut by plane.

Groove - GRV

Removes volume by using a spline tool.


Resolving Solids

Explode Boolean Tree - TRX

Resolves a selected solid into its basic parts. Solids used for adding or cutting are changed back to their original objects.


3D Filleting and Chamfering

When using these blending functions, first select the edges to be filleted (rounded) or chamfered. Selected edges must be continuous. Then specify the fillet radius or chamfer distance. Rounded or chamfered edges are kept if the solid changes during editing. The Fillet function resolves fillet overhangs and undercuts in most cases.


For filleting, you can select optionally:

3D Fillet - RN3, Ctrl + F
3D Chamfer - CH3, Ctrl + R

For chamfering, you can define a chamfer distance different for each side of the chamfered edge. If you select an edge of a threaded surface (for instance, end of screw or edge of threaded hole), optionally, the chamfer distance may correspond to the respective thread.


Deleting Solids

Delete Solids – RMS, Ctrl + D

Deletes selected solids. You can select entire solids as well as their components. For example, you can use this function to delete holes, fillets, ribs, etc. If such parts are selected, the solid will be regenerated, which may take time for complex objects.


Editing Shape of Solids

Edit Solid Element Shape

Edit Solid - MSO

This function allows you to:


Method of solid’s shape editing is selected from toolbar:

IconKeyUse
N/AEdit shape of basic solids or blending
N/ATransform elements within solid
N/ATranslate basic solids according to previously changed dimensions
N/AChange diameter of pipe or wire
N/AChange thickness of shell
EnterFinish selection of elements to be edited
N/AUndo edit change
EnterFinish editing

The Enter key (finish) is available either for “finish selection” or for “finish editing”.


Edit Solid Element Shape

Select a basic solid to be edited. After selecting the first object, you can select more same basic elements from solid. Then confirm selection. If more objects were selected, shape change is performed for all of them at once. For instance, you can change several holes, fillets or any same elements together. Following objects are considered as the same elements:

For instance, if the first selected object is a box, then other selected objects can be only boxes until the selection is finished. If the first object is a fillet, then next can be only fillets, etc. To distinguish how an object will be edited, the cursor is changed according a type of the object.


Cursor types:

CursorUse
Object cannot be selected – object belongs to different solid than first selected object or object is different than first solid
Spatial dimensions will be used for object’s shape modification
Object is fillet
Object is chamfer
2D creation profile will be edited
Object is shell, thickness will be changed
Object is pipe or wire, diameter(s) will be changed.
Object cannot be changed. Object is imported from STEP.
Object cannot be changed. Object is in active section.
Shell shape editing, spatial dimensions will be used.
Shell shape editing, fillet radius will be changed.
Shell shape editing, chamfer distance will be changed.
Shell shape editing, 2D creation profile will be edited.
Shell shape editing, element cannot be changed – object is different than first selected object or object is imported from STEP
Pipe segment editing, shape of straight segment or elbow will be changed.

As a basic solid, you can select solids used in Boolean operations - a solid added to another solid, or a cutting solid used to remove volume from another solid. As a basic solid, you cannot select any object imported from STEP. If the solid to be edited was created from a 2D profile, such as an Extrude or Revolve, you can edit the 2D profile. If the cursor passes over such an object during solid selection and the object is highlighted, the creating profile is also displayed. Together with this profile, its axes are displayed, too. This allows you easy orientation while editing the profile. After selecting the solid, the system switches to 2D drawing in 3D, and 2D editing functions are available. The profile is displayed with its original X and Y axes. When the editing is completed, click the icon on the Edit 2D Profile toolbar. Then reselect the profile’s 2D objects. See also Defining a 2D Profile. When editing 2D creation profile, you can leave the task only by clicking any icon in 2D Edit toolbar. This toolbar offers you to:


Rotated object created from a profile


Editing the object’s profile


Predefined solids (box, cylinder, pipe, etc.) or results of predefined Boolean operations (hole, etc.) can be comfortably edited using spatial dimensioning. Optionally, you can select dimensions definition in the table (window). Such an option allows you to change also basic parameters, like add a recess to a hole.


Example of the solid edited using spatial dimensions


Example of fillet editing


After specifying changes, the entire solid is regenerated. It is possible that editing will cause a situation in which the solid cannot be regenerated. Example: a 10mm hole drilled into a 20 x 20 x 20 cube. If the diameter of the hole changes to 50mm, the solid cannot be regenerated. In cases like these, you will receive an error message, and the Boolean tree remains unchanged.


Change Basic Solids Locations within the Entire Solid

See Transforming and Copying Solids for more details how to change object’s location. For changing the object’s location within entire solid, you can select object of any type (unlike the selection for shape editing), except the blending.


Translate basic solids according to previously changed dimensions

This option is available only if the translation distance and direction can be exactly determined. For instance, if you change height of a box, you can translate any other objects in direction of Z-axis of the box at a distance predefined as a difference of the previous and new height. Thus you can easily preserve position of any objects relative to changed side of the box.


If the option is available, an arrow in a respective direction is displayed. You can select objects to be translated and then click arrow or icon. You can also click the icon first and then select objects to be translated.


If you need only to change the solid element’s location use Transforming and Copying Solids instead.


Editing of Shells

Shell is created as offset patches connected to selected patches at a given thickness. You can change:

Selecting elements for a shape change, the cursor type is changed differently than for other ordinary solids - see Cursor types.


Example of the shell editing


Editing Pipes or Wires

Pipes or wires are created as a set of cylindrical segments and elbows.

You can change: