Create boundary patch in construction environment

Use Boundary Patch to create a planar or 3D surface from a closed boundary of edges. Apply conditions of tangent (G1) or contact (G0) to each edge, and preview the results before creating the patch. Once the first closed loop is selected, you can begin selections for a second loop.

Selections in an edge chain must be tangent continuous. To undo the last selection in an edge chain, right-click, and then select Undo Last Selection from the context menu. Repeat when necessary to remove additional edges. To remove an item from the list, select it and press Delete.

Note: Use primarily for imported surface data. For best results, avoid using boundary patch to create other features, such as sculpt, shell, and thicken/offset.

Create boundary patch from chain of edges

1. On the ribbon, click Construction tab Surface panel Boundary Patch .
2. Select a chain of tangent continuous edges which define a closed loop.
3. Click the arrow under Condition to select a boundary condition for each edge or set of selected edges. Edges are G0 by default.
   Note: Because continuous edges must have the same edge condition, all selected surface edges that are tangent or continuous with the previous edge are merged and listed as a single edge.
4. Optionally, select another closed loop.
5. Click OK to create the boundary patch feature.

Note: Region selection is limited to planar patches. For nonplanar regions, select the first loop, use Select Other to cycle through selectable geometry, and then click to select.

Tip:

• In the construction environment, the Boundary Patch command is not parametric. Some of the tangent conditions supported in the part environment are not supported in the construction environment.
• If you create a boundary patch with tangent constraints, avoid using supporting faces that are all perpendicular to one single imaginary plane. An angle other than 90 degrees is expected.
• Avoid creating a boundary patch on construction geometry that consists of a single segment closed curve (circle, ellipse, or closed spline).

Multi-threading

The Boundary Patch feature takes advantage of multi-threading on machines with more than one processor or with a multi-core processor. It uses multi-threading based upon the OMP_NUM_THREADS environment variable. The Autodesk Inventor LT installer sets this variable if it is not already defined.

You can edit the value of this variable to influence the number of threads used by Boundary Patch. By default, the Autodesk Inventor LT installer sets the value to match the number of logical processors on the machine.

Settings for OMP_NUM_THREADS environment variable

Although the Autodesk Inventor LT default is expected to be the best choice, in some cases the performance of the Boundary Patch command can be improved by reducing the value of the OMP_NUM_THREADS environment variable. To disable multi-threading in Boundary Patch entirely, set OMP_NUM_THREADS to 1. You can set the OMP_NUM_THREADS environment variable from a command prompt or the Control Panel.