Repetitve subtraction

I have a sphere and a bunch of pyramids that looks like this:

I want to subtract the pyramids from the sphere. I made the pyramids into a group and tried to subtract the group from the sphere but sketchup says I need two solids. TWO SOLIDS ONLY.

so i ungrouped the cluster of pyramids and started subtracting each pyramid from the sphere like so:

Isnt there a way to subtract all the pyramids from the sphere at once?

What version of SketchUp are you using? Please complete/update your profile.

Upload the model so we can see exactly what you are working with.

how/where do i upload the model? BTW, I can start w a bunch of pyramids and start subtracting them one by one from the sphere ok. But if I try and save my work, sketchup complains that there is a problem and it wants to fix it. If I fix the problem, save , quit, and reopen then it will not allow me to continue my work-rather it gives me the error dialog pictured in the second image above.

Same way you uploaded the image.

Probably due to the dimensions of the model.

Select all the pyramids, explode them and while still selected immediately make a group
Then perform the solid action

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My attempt (I replaced the model, wasn’t sure what the end result is supposed to be like, so I did a couple of variations).

pyramids.skp (671.0 KB)

Thank you colin. Yes I tried to make the sphere with windows cut out of it. This is an attempt at reverse projective geometry. A grid on a plane projected into the center of a sphere. I tried to reproduce what you did. Here is a pic:

On the left is the assembly of pyramids I want to subtract from the sphere.
The next three images show the construction of the hollow sphere. Basically I create an annulus first. Then I create a circle orthogonal to it. Then I click on the circle, click follow me tool, and then click on the annulus to get the hollow sphere.

Finally I move the sphere into position but for the life of me cannot figure out how to subtract the pyramids from the sphere. I keep getting the ‘not a solid’ error dialog. Attached is the model I have. I downloaded your model and yes it is very close to what I am trying to achieve. Interestingly, when I move the viewpoint into the middle of your sphere, nothing is visible outside

.pyr4.skp (3.3 MB)

I went back to the beginning and created a simple hollow sphere. I then subtract a few pyramids from it one by one. But then, I noticed my sphere wasnt hollow any more but each cavity made by a pyramid subtraction left walls in the channel. I then have to delete each individual wall-way too much work.

It looks a little like the spaceship from 2001 A space odyssey.
Here is the model

pyr4first.skp (2.0 MB)

I did a screen recording that also shows how I did the pyramids using built in tools. You should watch the dimensions box, that’s where a lot of what I did goes on. When the sphere disappears it’s because I cut it, to paste in place later on. I used keyboard shortcuts quite a bit, one of which is a custom one. I have ctrl-shift-z to Zoom Selection, it’s very handy. All done using my MacBook Pro trackpad.

For the moment going to YouTube will show better quality. I expect it will look better here later on.