Hello everybody. I have a cube in a file with stl format. I want to cut a central sphere from that cube. How can I do this?

If it's only a cube get the dimension of the side and then do it in any 3d design program.
Otherwise use any 3d design program that can load an STL file (which is most of them) and then subtract the sphere.

In OpenSCAD:

side = 20;

difference()
{
	cube([side,side,side], true);
	sphere(r=side/3, center=true, $fn=100);
	
	translate([-side/2,0,0])
		cube([side,side*2,side*2], true);
}

The second cube is subracted to cut the cube in half so you can see that indeed the sphere has been cut out of the inside!

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Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
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