Creating a hole in the mechanical part

In the previous sections we drew the profile of the part and we created the surface. In this section we will make a hole, an octagon with a radius of 10 units, in the surface of the part. First we will draw the octagon.

• Select from the menu Geometry->Create->Object->Polygon to create a regular polygon.
• Enter 8 as the number of sides of the polygon.
• Enter (0,0,0) as the center of the polygon. (use Ctrl-a keys to swap to select new point mode if required)
• Select Positive Z as the normal of the polygon, this mean a normal direction (0,0,1)
• Enter 10 as the radius of the polygon and press ENTER. Press ESC to finish the action.

We get the result as shown in following figure. As we only need the boundary we should remove the associated surface. Select the option Geometry->Delete->Surfaces and then select the surface of the octagon. Press ESC to finish.

Note: check that 'Also lower entities' is not checked in the delete menu, otherwise also the lines and points of the surface will be deleted.