Intersecting A Component With Another Component (Or Group)

Hi. I had a question.

I’m attempting to make my model 3D printable and in my efforts to make everything manifold I’ve decided to replace some of my geometry with a component.

What I have is a bunch of guardrail posts that I want to join with the terrain. Consider the following images:


Can I intersect the guardrail component with the terrain group? My plan is to add the guardrail post components to the terrain group.

You can do that. What you really need to have happen is the terrain cuts the post and the post cuts the terrain. If the posts are going to becoming part of the terrain, the post geometry needs to be in the same context as the terrain. You can explode the post components, select the geometry (it’ll already be selected after exploding), hit Edit>Cut or the appropriate keyboard shortcut. Then open the terrain group for editing and hit Edit>Paste in place. Next, while the post geometry is still selected, right click and choose Intersect Faces>With Model. Then delete the bottom of the post and the face skinning over the hole where the post comes through.

It should look something like this.

Hi Dave. I’ll give it a go later on and let you know how it goes.

It does not work.

For some reason I have to use Intersect Faces > Selection to get it to work, and that involves selecting the faces on the terrain that it’s going through.

But, it works that way at least…so everything is zen.

It will work if you do it exactly as I wrote. I tested it as I wrote to make sure I didn’t miss anything and posted the result in the screen shot. But, since you got it to work, all is good.

The posts “drive” into the terrain where it splits angles, and for some reason those lines don’t get intersected and so I have to do it using the “Selection” method.

Do you happen to know why SketchUp puts a bunch of superflous hidden lines on faces after intersecting? I simply delete them; is there any hazards of doing this?

No. Try erasing those hidden edges. Do you lose faces? If so, that would be an indication of planarity issue with the larger loop of edges.

I delete the edges and nothing happens except the paint “shifts” a bit. Not sure if that’s something to worry about, but it is curious…