Solid Intersect Tool Not Working as Expected



I have played around with SketchUp in the past, but I am very new to the Pro tools in the trial.

I had an idea to easily create a 3D head using only three faces and pushing/pulling to define the space where they either intersect or do not intersect (subtract), and I found that the intersect tool works well for this. I successfully demonstrated it using a very rough sketch of a human face, and again using basic shapes like circles.

So I’m familiar with how the intersect tool is supposed to work, thanks to the great tutorials here and elsewhere on creating solid objects.

However, now I tried to recreate this with a sketch of my ugly face, and the tool is not working as expected. I have three solid components with no loose geometry. When I click them and select Solid Tools > Intersect, I get a variety of different results, sometimes depending on the order that I click them. But one thing’s for sure: none of the results is what I expect.

Can any of you SU gurus take a look at my file and see why the intersection is not working? Is it something with my version or the fact that I’m just a trial user of Pro?


Hi ,Sketch does not form faces smaller than about mm square and so just scale up your model to about 100x times and try that .



As Phil says, scale up by 100.
Temporarily move one component to the side,
Then apply (for instance) the split tool on both the other components.
In the result delete the groups, the parts (groups) you don’t need, leaving the inner result group.
Move the first component in place again.

Repeat the steps above with the inner result group and that third component.

In the end you can scale down the result.

But be aware that it might be impossible to work on the result at original scale. As soon endpoints get too close, they’ll merge. So keep working/carving/etc. in the scaled up result if needed.


ide note, Some solid tools do change behaviour according to the order of selection… If A was a rod that passed right through a cube B, then for example subtracting A from B gets you a cbe with a hole, whereas subbing B from A gets 2 pieces of rod, so the order of selection can be important


Very helpful posts, all of them! I wasn’t aware of the scaling issue and will be mindful of that in the future.