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Hello Leonardo,

What you did in that screenshot is that you rotated the axis of the sphere; this is why you are not getting the output you expected.

As a side note, you are specifying those rotation angles in degrees right now: notice the "deg" unit to the right of those two text fields.

I assume that you want the angles theta to be between 0 and pi radian and phi to be between 0 and pi/2 radian, i.e. you would like to build a quarter of spheres. If so, you can achieve that by adding a couple of blocks in the geometry and using boolean operations to remove from the geometry the parts of the spheres that overlap with the blocks.

Best regards,

Jeff

There is more than one way to do this. But since you are interested in angle ranges that correspond to axes, this is really quite simple. 1. Create a sphere (volume) with the outer radius. 2. Create a sphere (volume) with the inner radius. 3. Using a Boolean operation (Difference), subtract the smaller sphere from the larger sphere. This gives you a spherical shell. (Alternatively, you can employ Layers, within the Sphere setting.) 4. Create a rectangular Block (Note: default has corner at the origin, but can be changed). 5. Using a Boolean operation (Intersection), intersect the block with your spherical shell. If you do all this correctly, you're done.

Alternatively, you could specify a workplane, create two circles (areas), take the difference, and revolve that into 3D space, appropriately. Note that in the workplane, you can specify angle constraints on the circles if you want (making them more like pie-wedges than circles).

There are other more generally-applicable methods you could apply, but your shape is so simple that I wouldn't bother to try those here.

Ah, I see that Jeff got to this one just before me. :)

There is more than one way to do this. But since you are interested in angle ranges that correspond to axes, this is really quite simple. 1. Create a sphere (volume) with the outer radius. 2. Create a sphere (volume) with the inner radius. 3. Using a Boolean operation (Difference), subtract the smaller sphere from the larger sphere. This gives you a spherical shell. (Alternatively, you can employ Layers, within the Sphere setting.) 4. Create a rectangular Block (Note: default has corner at the origin, but can be changed). 5. Using a Boolean operation (Intersection), intersect the block with your spherical shell. If you do all this correctly, you're done.

Alternatively, you could specify a workplane, create two circles (areas), take the difference, and revolve that into 3D space, appropriately. Note that in the workplane, you can specify angle constraints on the circles if you want (making them more like pie-wedges than circles).

There are other more generally-applicable methods you could apply, but your shape is so simple that I wouldn't bother to try those here.

Ah, I see that Jeff got to this one just before me. :)

Hello @RobertKoslover thank you very much for your reply; I did the intersection between a rectangular block and the rest so that the result is half sphere; now do I need a new block to remove hal f of the half sphere (see image please)?

You're welcome. If you want (or need) to cut it in half again, go ahead. You can make as many blocks (or other shapes) and apply as many Boolean intersections (or other) operations as you wish.