Slice a model into smaller pieces - for easier 3D printing

Hi, my students are looking to slice a model they have made into smaller pieces for easier 3D printing. We are experimenting with drawing a slicing plane and inserting it where we want the break to be, but we can’t figure out how to separate the two pieces. Can someone help? Thanks much, Rob

I’ve made a plugin that does just this: However I’m not sure how well suited extension warehouse licenses are for a classroom. each license can only be used on 2 computers. For now there are no group licenses or even group discounts supported by extension warehouse.

It can of course also be done manually but it’s a bit of more work. To do this you first need everything in the model to be grouped (so you can draw new geometry without it sticking to what is already drawn). Then draw a face somewhere through the model. Then intersect this face (Right click > Intersect Faces > With Model). Then you have to carefully select the geometry on either side of the the face and make two groups. Finally you have to close the cut surface in each of the two groups by drawing new faces.

1 Like

Thanks eneroth3, SU4Schools doesn’t accept plugins as far as I can tell. And for our purchasing for our classroom won’t be possible anyway. Thank you for the alternate manual option. I’ve followed those directions and gotten as far as Intersect the face. It does indeed create two separate elements I can highlight, but I cannot seem to move them apart from each other. Is there a step I am missing? When you say “make two groups” what does that entail? Thanks so much.

at the moment you cannot use extensions with SU for School or SketchUp Free…

another manual method is to select portions, group those, add faces to make solid then reposition for your print layout…

if you add a couple of example models ‘we’ could make some gifs showing different methods…


here is an animation of a manual process you can try.


  1. Break the object up into segments and remove unneeded geometry
  2. Make each segment into a group
  3. Make each group a solid by adding the missing face that will make it manifold.

Hope this helps


Sorry, I didn’t see the category and assumed you were using the desktop version in class.

Chri’s Gif is a good illustration though!

Hi Chris,
This is super helpful. That said, there are a few keystrokes happening in here that are just beyond my current skillset. How did you add the missing face so quickly on the individual blocks?

Also, if you were to 3D print those, would those blocks be hollow or solid? If hollow, would those surfaces be thick enough to print? If not, how would you achieve a better printing thickness on those.

Thanks so much. This is such a great tool, but as yet there aren’t enough training modules to really own it.

Have a look at how to create an array with SketchUp

In my example, I also used an inference lock with a reference to the backplane to establish the first copy quickly.

“… if you were to 3D print those, would those blocks be hollow or solid?”

The individual elements I created would be considered solid. I didnt show it in the animation but each of them will show as a SOLID with a volume in the Entity Info dialog in SketchUp.


1 Like

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.