Intersect with model doesn't work as I expected

Hi there.

I’m following this tutorial

and I’m trying to intersect this shapes


When it does, it seems to work as I expected.


At first I thought it was the bottom part.


But even if I fix that or I intersect with two rectangles higher the problem is the same when I start to delete son edges.


Some help to identify what is happening in the model?

Thanks in advance.

leg_problem.skp (176.8 KB)

Maybe you didn’t intersect the vertical faces with the bottom of the leg correctly.

This worked for me after recreating the leg.

Move the cutter into place. I made the leg wider than needed to make cleanup easier. No reason to be stingy with the geometry. the waste doesn’t cost anything.

I placed the cutting surfaces in place over the leg component. I moved it down slightly to ensure that the bottom faces would get cut during the Intersection.

Cut the cutters to the clipboard, open the leg component for editing, paste the cutting faces in place, select all.

Intersect Faces>With Selection. Erase the unneeded parts of the cutting faces, select the waste outboard of the cuts.

Delete the waste and the faces skinning over the opening. Done.


Hmmmm, interesting, it works like you tell me but … I don’t understand why:

  1. if you paste in place inside the component the cutters and apply intersect with selection works
  2. if you open the component, and choose intersect with the model (the cutters are outside) it doesn’t work.

Of course it doesn’t work correctly if you leave the cutters outside the component. Why would you do that? You need the cutters inside the component so that they get cut by the leg geometry to leave the faces skinning over the edges of the leg. The faces shown selected in the screen grab below as well as their counterparts on the opposite side are the remains of the cutting faces.

If you leave the cutting faces outside the component, you won’t get those faces.

Hmmmm, I think I got the point.
Those faces I miss are made belongs to the cutting faces, good.

Thank you so much.


Intersect with doesn’t spawn new faces, just add edges where faces intersect.

Yep, I’m pretty out of practice and my last sentence had some grammar mistakes. The conclusion is as you said:
1 - ‘Intersect with’ doesn’t create new faces
2 - I was missing some faces but those faces belongs to the cutter object and that’s why I have to work with them at same level (and not outside the component as I was doing)