Cutting a face into a sphere

Ok, i have created a sphere, and now i want to make part of it, transparent like a window. this will keep it a solid but will allow me to either see in or make it a fully tinted window. here is the image of what i am modeling next, or at least attempting to haha. But before i even start this project, i want to learn to make a window, like in the pic, and make it transparent or at least the black color. same shape as the blackportion if possible, or at least close to it.



I think you could do this with native SketchUp tools. First, make the sphere a component and open it for editing. Then go to View>Hidden Geometry to show the network of rectangles and triangles that form a surface like the sphere. Then trace over the appropriate hidden lines to outline the part you want to make transparent. Turn off Hidden Geometry. double-click in the area you’ve outlined and go to Edit>Cut. Close the component, then go to Edit>Paste in Place to place the transparent part back in place. Make it a component, too. Then you can apply whatever textures you want over each of the components.
One of the SketchUp sages may have a simpler solution, but I hope this helps.

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thats a great idea. another tool i dont use and now will. HIDDEN GEOMETRY! thanks for that. ill wait for others to chime in as well. Right now, im done with the fuseluge, taile, and fins. just working on the wind now and im having issues with that. ill post that next once i have figured out the window piece.



ok, lines are completly closed but a surface is not forming. its hallow:

As suggested you can select parts and group, or another way might be to use the solid tools.
the issue with the first might be that you will have a limit to the rectilinear faces of the sphere structure for the window shape without radius corners ( although could be drawn) but the solid tools might allow you to more easily get the shape of the window you want first?

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My simple version.
Really bad upload times for me.


thats cool way of using native tools to do this. I will try out all these methods and keep them handy.

I have no dims to work off of, just the photo. alot of this is new to me and im doing this so i can think of how to model on the fly sort of speak haha.

is that booltools or solid tools?

i couldnt get my eneroth to leave the profile like yours so i just did it native style,. BUT it made it not a solid either with 5 surface boarders i cant see haha. probably tiny face. need to scale up…

The original shape just looks like a sphere cut thus. Looks like you’re on your way.

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can you show how you did that please? or is it the same way i did it, just used an arc instead of a rectangle at the top?

thank you

I used the lines of the sphere. Before you rotate from vertical, it’s easy to select the top with hidden geometry showing, and group it for the window. Then you can cut another half circle from the remainder using a cylinder and “Intersect faces”. Do that part without hidden geometry so you have the surface in one piece. Then you can select that surface (not the edges) and “cut” it to paste in place-in-place inside the glass group.

A different way with this extension:

It was booltools, but should get you the same results?
I’d still be inclined to radius the corners of your shape for an aircraft ?

Awesome. thanks:) I will add in the radii later today. I agree, it looks better. Well, and it actually has a purpose as well

I finally got it working last night. Im still not used to the tiny face issue. I kept getting holes in the mesh. I had to scale it by 10,000 in order for it to work haha.

i will be looking at that extension. it looks like it will come in handy. I will be working on the wings while im at work today… hopefully.

one thing i have noticed, its been difficult to make the horizontal stableizer. its supposed to have the vertical pices be at a slight angle and look as if it were “folded, or bent” out of a single piece of material, rather than just straight vertical like mine haha

so far, this is what i have:

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Oh, man. i tried to select the lines last night on my sphere. When i had them all selected, it would not close for some reason. Thats when i moved to the solid tools option.

so, to understand your approach, you selected the lines on the sphere, then it will create a face, then you group it?


Not sure if this is what you’re asking but if it helps … showing hidden geometry


You can use the eraser tool + ctrl + shift to make some edges visible (and just ctrl to hide them again):


Hidden geometry off


And you can go back to hidden geometry on and keep editing, you need to keep in mind that a face is closed when all its vertices are connected and they’re coplanar (they sare the same plane, 3 dots will always be coplanar but not more). You can make little editions like arcs in the hidden geometry.


Then erase tool + ctrl to hide some edges, turn hidden geometry off again




hmmm, that is pretty close to what i did. I used the line tool to connect the window face together. maybe i lifted the line upp off of the sphere at some point. Ill try this now and see what happens.

well, and it was 2am when i was working on this. i was pretty tired haha

Huge thanks my friend


WOW!!! ok, the eraser tool plus ctrl plus shift, worked great. I have read the instructor before and it says it unsoftens and unsmooths when using that combo. I thought it ment something else, not that it would actually select the lines haha

here is one i did. not exactly perfect, but kind of cool.

I think when you are tracing you are skipping over vertices. You would need to trace to exisiting ones along the line otherwise you will get mismatch. Or draw on faces.

If you want windscreen to match/mesh exactly to body they would have to share the same vertices.

Ok, so using the arc tool like i was using, was not going to work then haha

It’s important to remember that all geometry is a simple matrix of edges and faces, when the edges between faces are smoothed you get ‘surfaces’. So unsmooth or harden the edges needed to create the surfaces you want. Tracing an edge will tend to create a face where you don’t want it, in this case making slices across the sphere.

The Eraser tool with ctrl and shift will unsoften edges to create the surfaces you need. Extra shapes/cuts need to be on single faces to work. So an edge drawn across two faces makes another face rather than cutting the face you want. When you intersect one shape with another it adds the edges on the individual faces connecting the existing geometry matrix.


Box, thanks for that demo and awesome explanation of how surfaces work.

I am seeing how using the arc tool to follow the lines on the sphere is not going to work. It basically weaves inbetween the outer and inner surfaces. But using the eraser tool to select the individual lines by hardening, ensures that they are all connedted one to another.

I have been toying around with this and also using the solid tools method. Both give excelent results