Manifold errors when export to STL's using SketchUp Web (Free)


I’m new to 3D printing and new to SketchUp.

I’ve been using SketchUp Web (Free) to do some modeling for some hobby 3D printing. When I export a file as an STL, and load it in my slicer (Cura), it gives me a manifold error when I attempt to slice. Based on some initial googling, it seems as if my models are not actually solids.

Anyone have any suggestions they can throw my way on how I can create solid models out of my incomplete models while using SketchUp Web (Free)?


It kind of depends on the model and why it isn’t manifold. Maybe you could share one of your SketchUp models so we can see what you’re working with?

In general, you need to have a watertight solid. The simple way to know that you’ve met that is to create a group or component of the geometry and check to see that it is reported as solid in Entity Info.

The simple definition of a solid is that every edge is share by exactly two faces, no more and no less. So no edges without faces, holes in the shape, and no internal faces.


See attached for the failing SKP files. SketchUp lets me convert them to STL’s but when I go to slice them in Cura, I get a manifold error.

Let me know if you have any success in identifying my issue or in creating a printable STL?

I’d attach the failing STL files, but the forum only lets me attach two files so I thought the SKP files would be preferred and I didn’t want to spam the thread- if you’d like to see the STL’s too I’d be happy to send those over.

So sorry! Did my edit come through?

Nope. No .skp file attached.

There is no inherrent requirement that the geometry be manifold in order to create the .stl file so there’s no reason that SketchUp’s .stl exporter should stop you. It’s Cura that requires the manifold geometry so the error is in the right place.

There’s no need to attach the .stl files. It’s the .skp file that will provide the answers you need.

Take Three!

Uploading: SmallCards.skp…

Yeah, I get that SketchUp can export incomplete files with manifold errors and that they need to be pretty in order for Cura to do its thing.

Let me know if these uploads work/don’t work?

In the event, I still haven’t been able to figure out how to upload files Google Drive File with 2x SKP files.

The object I see when I open your file looks fine. It reports solid in both Entity Info and Solid Inspector². The problem will be the other stuff in your file. You have some hidden components. If you exported with Free, I don’t think you have the option of whether to export hidden geometry so that might be the problem.

Without an outliner window, you’re working blind so you’d have to remember that the stuff was still there, or turn on hidden geometry to see it.

I deleted all the hidden objects and purged unused stuff. This reduced your file size by 99.8% ! Your file attachment wouldn’t work as it was too big for the forum, but if you’d trimmed it down first, it would have worked fine. Not everyone wants to download such big files either, especially when most of it wasn’t actually the content that mattered.

ModularMap_gm.skp (223.3 KB)

Your other file had one stray line in the object that was visible. There was a similar huge reduction in file size after deleting the hidden objects and purging.

SmallCards_gm.skp (192.3 KB)

Thanks so much!