Trimming with keep\remove elements.

How to improve your trim and split operations?

Whenever you create a Split or Trim operation, it is a good practice to indicate the element to be removed or the element to be kept. During modifications on your part, trimming elements may change their orientation, which in turn will change the result of trimming. To make your design more robust and easier to modify follow this method.

Example
In this case a hole is created on a surface. As hole always has a center point, it can be used in spliting operation. First see how it works without defining "element to be removed" - Fig.1.

Fig.1

Now try with "element to be removed" - Fig.2.

Fig.2

As you can see, changing orientation of the cutting element does not affect the result - Fig.3.

Fig.3