Step 1. On the home screen, navigate to "Library" and click "Add Custom Hardware".

Step 2. Import 3D Model.

Step 3. Select the "Intersection of two lines" add point tool. Select the inside edge of one face and then the other face. This will create a point in the corner of the extrusion.

Inside edge

Step 4. On this new point add a UCS Placement and set the ZYX correctly, to make sure you have it correct, set the x axis along one of the edge you set selected in the previous step. You can also rotate the axis if necessary.

Step 5. Once you are happy with your ZYX, click the green cross.

Step 6. In the tool bar select the "Material tool" and select "Aluminium".

Step 7. In the tool bar select "appearance" and select the finish of your brace.

Step 8. Select "Add to library", fill out the required information and click on the "Create" button.