In the Geometry toolbar, Conversions menu, click Thicken () to convert a surface object to a solid object by giving it a thickness in the normal direction. You can also right-click the Geometry node and add this node from the Conversions submenu.

From the Input objects list, choose Manual (default) to select the objects you want to thicken in the Graphics window. Click the Activate Selection button to toggle between turning ON and OFF the Input objects selections. Alternatively, choose All objects to select all objects or choose All nonconstruction objects to automatically select all objects that have not been marked as Construction Geometry. If the geometry sequence includes user-defined selections above the Thicken node, these will also be available in the Input objects list. Each input object is thickened independently.

Select the Keep input objects checkbox to use the selected geometry objects for further geometry operations.

Select an Offset — Symmetric (the default) or Asymmetric.

If Symmetric is selected enter a Total thickness.

If Asymmetric is selected enter an Upside thickness and a Downside thickness.

Select the Fillet offset edges checkbox to fillet each convex edge joining two offset faces, using the offset distance as the fillet radius. This option applies only when the offset is single sided; that is, when either the up or down thickness is set to 0.

For either choice, select the Direction of side faces — Normal (the default) or Vector. For Vector, and based on space dimension, enter values or expressions for x, y, and z (SI unit: m). Note that this setting influences only the direction of the side faces, the specified thickness is always applied in the normal direction.

If you want to make the resulting entities contribute to a cumulative selection, select a cumulative selection from the Contribute to list (the default, None, gives no contribution), or click the New button to create a new cumulative selection (see Cumulative Selections in the COMSOL Multiphysics Reference Manual).

Select the Resulting objects selection checkbox to create predefined selections (for all levels — objects, domains, boundaries, edges, and points — that are applicable) in subsequent nodes in the geometry sequence. To also make all or one of the types of resulting entities (domains, boundaries, edges, and points) that the resulting objects consist of available as selections in all applicable selection lists (in physics and materials settings, for example), choose an option from the Show in physics list: All levels, Domain selection, Boundary selection, Edge selection, or Point selection. The default is Domain selection, which is suitable for use with materials and physics defined in domains. For use with a boundary condition, for example, choose Boundary selection. These selections do not appear as separate selection nodes in the model tree. Select Off to not make any selection available outside of the geometry sequence.

If you have Named Selections that include entities on the input objects, select the Propagate selections to resulting objects (selected by default) checkbox to update the selections to corresponding entities on the output objects, when possible. Clear the checkbox to not propagate the selection to the resulting objects. Selecting this option can be useful in combination with selecting the Keep input objects checkbox so that the selections refer only to the input objects.

From the Construction geometry list choose On to make the resulting objects available only in the feature’s geometry sequence. The default option Inherit from input means that the resulting objects become construction geometry if all input objects are construction geometry. Choose Off to never output construction geometry objects. For more information see Construction Geometry in the COMSOL Multiphysics Reference Manual.