3D Printing from CAD Mapper. Can I turn the road outlines into indentations? Why can't I do it with push/pull?

Hello! I’m very new to SketchUp and I’m trying to learn!

I have a model that I exported using cadmapper.com of a small city. I exported the roads as outlines. I used the Eneroth Terrain Volume Extension to add thickness to the base for 3D printing and then manually adjusted the heights of the buildings using the push/pull tool.

I currently have both roads and water that I would like to give negative height to, so that they show as “indentations” in the base of the 3d print. The ultimate goal would be to have the water be the very first layer so that I can use blue filament for that, and then switch the filament color to white for the rest of the model. I would also like to be able to see the roads in the 3D print, which is why I want them indented in the base.

Pardon my unfamiliarly, but it seems like the roads are a different type of object than the buildings and I’m unable to select them and push/pull them the same way. Is there any way to make the roads push a little into the surface?

Since I’m new to this, a video of how to do it would be awesome! Thanks in advance.

I’ve attached a picture and the file to this post.
navy-yard-v1.skp (464.7 KB)

Roads are outlines, just outlines. they don’t have faces.

therefore, you can’t extrude them. First, you’ll need to close them into faces and/or retrace some of their sides to make faces that you can extrude. Eneroth has a tool for that, “face maker” or something.

since your terrain is not flat, you’ll still have a small issue : pushpull works with single flat faces, not multiple smoothen ones.

If you simply want to have the road lines on the terrain, using the sandbox tools, you can simply drape the road to the terrain (5th icon)

If you want the roads to be thicker on top of the terrain, you can use fredo6’s pushpull extension (a mega pushpull that allows you to push several faces at once, even smooth ones). You could also duplicate your terrain, and keep only the roads that you draped on it. and treat it as you treated the terrain with eneroth terrain volume extension. then simply put the roads on top of the terrain.

if you want the roads to be deeper, same idea as before, but you might need to do some solids operations.

I need to finish something and I’ll repost with some screenshots of what you could consider doing.

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I start from a small Cadmapper file.
The terrain itself can be thickened using an extension, or simply by drawing 4 vertical, one at each corner, and making a flat face at the bottom.

Right now I have the terrain in one group, and the road outlines in an other group.

I didn’t remember if the outline were gonna be flat or not, and no. they are curved according to the terrain. notice how I had to extend a bit the road on the right so it goes beyond the terrain.simply went in top view, traced a small extension with the line tool.

So first, I’ll drape the road on the terrain. Sandbox tool, I’ll use the 5th one, the circle

Capture d’écran 2023-08-11 à 20.35.46

the top road is now useless. cya top road.
Using Fredo6’s Curviloft extension, I could have made the top road in a soft face, but I don’t have it on this machine.

And here I get my terrain AND the road as a soft face (again, curviloft would make the same without draping). I simply duplicated my terrain, and deleted all that wasn’t the road.

Here, several solution, one result to reach. You could use eneroth terrain tool, I’ll use the joint pushpull tool.

For the terrain, I simply draw verticals at each corner, and then close with a flat rectangle.

The road has been thickened using the tool of choice.

Capture d’écran 2023-08-11 à 20.28.40
If I group my road and place it on top of its trace, voilà, a 3d road. These are separate groups, I could however merge them using the solid tools if needed. Or even do the joint pushpull directly on the terrain in the first place.

need it deep ? after all, roads are not giant 50cm steps above the ground.

either take your road group and lower it a bit in the terrain. if both are solid groups, you can use the solid tool substract to make a cut. result is like that :

If you have joint pushpull extension, you can do it directly on the terrain using the trace :
(and I just remembered I switched my Extension in french, neat ! :slight_smile: )

Capture d’écran 2023-08-11 à 20.30.49

The joint pushpull version is my favourite. But it’s a paid extension. Using eneroth terrain tool and the solid tools (both free) you should arrive to a similar result, either in positive or negative.

Same can be made with buildings. If you plan on printing buildings separately, you can place them, using the solid tools, make holes in your terrain that will accommodate them.