Creating holes in model


OK - google search isn’t doing it for me.
I am trying to create a 3D print model.
I have 2 questions (to start).

  1. For 3D print purposes is the model suppose to be “solid”, or is that supplied by the infill of the print software? The test made it waterproof and I assume it is still hollow as it was when I submitted it.

  2. I have created something using other files - probably not very efficiently.
    When I submitted to test it was a sinking boat - not very waterproof.
    So they waterproofed it and now holes that I had in it are closed. How do I create holes in this model? It seems to resist editing for one - for another I can’t figure out how to make a waterproof hole.



In Sketchup, most objects are grouped once they become a solid. To answer your first question, the solid will become editable when you double click on the object. Remember that grouped objects are made of multiple pieces. If you need to edit a face, and the object won’t let you, double click on the face until everything else greys out.

For your second question, select the face you want the hole in, and draw a circle the size of the hole you want, then push/pull to the opposite surface.

If you wish, I can post some screenshots of what I am talking about.




It’s difficult to help without an image or a model…


maybe it is symantics -
What does SOLID actually mean?
The vision I have of solid is like a brick. Does it really mean like a balloon in this context?
IE: “solid” == “waterproof”?
It would seem to me that if it is like a brick it would be printed at 100% infill.
Whereas “waterproof” would allow u to select the % infill.

OK I can post the file - if I can figure out how - but just take a box (which would be waterproof) and put a screw hole thru it.

The fixed file that was created still shows the outline on the surface of the holes I made in the leaky part - but they are not holes thru the part. And I assume the part is still hollow inside.



what u r saying is that grouping them creates a solid object?
I’ll have to try that again to see if it becomes waterproof. I thought I did that but maybe not.

I did that push on the original part but I guess because it wasn’t solid the hole had no walls.
It may be that I am just having trouble getting to edit the fixed waterproof part.
When I try so many things I just forget what I have tried.

If I create a cube

  • draw sq then push a surface -
    1st - is that going to be waterproof or do I have to do something else?

2nd - if I draw a circle and push it to the other surface (which I think I did) how do I do that and see a wall inside the hole - as in drilling a hole thru a 2x4 instead of a cardboard box?


OK, this is what I am doing-
I create a cube
I make it a group
I draw a circle on a face and push it out.
I delete the core I pushed out the back
What I have is a hole in the side I drew the circle on and no hole on the back side where I deleted the core and I can see the inside of the box from the front hole.

Obviously, not what I want - So how do I create a watertight cube with a hole thru it?


Hello Bill,

SketchUp does not have a concept of solid. Every solid looking model in SketchUp is actually a hollow (similar to the box of cardboard).

Now,when you are pushed the circular face it simply created a cylinder face, which crossed the boundary of the opposite face. SketchUp does not intersect the cylinder face and the plane face of the box to create a new edge at the intersection. Actually the cylinder face is one face starting at the top. So when you are deleting the cylinder face (core) there is a hole in one face and nothing at another.

If you want to create an model which looks like a clean hole through the model you can use inferencing and stop pushing the face exactly at the other face.

Hope this helps.


COOOOL, I stopped when I saw that red dot and it is perfect.
Didn’t even have to delete the core.
I’m not sure that make sense to me but it works.


The definition of solid model is that every edge of the model is connected to exactly 2 faces.
Extra condition of Sketchup is that the model should be group or component.
The easy way to know if the model is solid and why not is to monitor the model with SuSolid plugin.Also free version is enough.


Understanding Solid Objects in SketchUp — Aidan Chopra