4. Dumbbell

In the OpenSCAD environment, model a dumbbell.

Use three cylinders, positioning them as needed.

For rotating the cylinders, use the "rotate" command.

To avoid rotating each cylinder separately, group all the cylinders together using the "union" command.

Example help:


union(){
    rotation{
        cylinder
        cylinder
        translation
        cylinder
    } 
}


 Please note that this help is just an example!