Autodesk Inventor – Back to Basics - Intersect Extrude

By Chris Smith

Introduction
In a majority of cases when using the extrude tool most users are inclined to use either Join or Cut as the method of choice. This is likely due to being able to easily picture adding or removing material from a model on screen. Another often overlooked extruding method is available in the tool and can help users save time when creating their models. In this blog I will give a quick example of the Intersect method in the Extrude tool to highlight the benefits of using this option.

Example
In this example I am making a simple bracket that will be machined from a solid block. I have already extruded the ‘U’ profile and added 2 mounting holes. The sizes are shown below if you would like to follow along.

From here I can add the profile sketch to the side face of the bracket. This could be a 2D underlay from a supplier dwg or legacy AutoCAD data or just a sketch done in Inventor. Again, the sketch is dimensioned below.

From this point, most users would use the Cut extrusion method to remove the profiles around the outside and the holes and slot. However, you may have noticed a potential issue.

Looking again at the sketch above, we can see that the edge has not been projected. This is due to how the 75mm line was created (drawn from the 0,0,0 point instead of projecting the edge), and would prevent us from extruding that profile. This is not a big deal however and we can project the edge in the sketch (Edit sketch > Project geometry > Save sketch).

Now our sketch is complete, we can start to cut out the profiles we do not want. I have numbered the profiles below – 6 in total.

With some chamfers to remove hard edges we have our finished bracket.

So, let’s look at the Intersect tool and see how it can improve this process. Let’s return to the point where we added the profile sketch but before we projected the back edge.

This time, I will select the actual profile in the extrude tool but change the method to intersect.

We can see from the preview that we get the same results as the cut method above but without all the additional steps/clicks, saving time and effort while creating our models.