I've made a model of the KitcheAid mixer and experienced a Boolean error that just does not work. Whenever I try to do a Union on the two solids as shown in the attached images, Plasticity does a subtraction and the result is as shown in Image 3. I've tried modifying the cylinder so that it protrudes into the top of the units housing but it just doesn't work and if I create a cube on the bottom of it, I still get a subtraction. Don't know if there are any ideas out there, but this one just seems impossible to work. As you can see the cylinder turns blue ready for the union, but the result is fresh hole in the housing.