Hello,

There is some little problem in your model that prevent moi to create fillets here :
Tiny edges like this dont help :




So I rebuild the model, extracting to original revolve profile, and extend the bottom control point.




Then I create the revolve, and bollean diff 2 boxes




I have attached the resulting .3dm ... you shouldnt have any trouble to fillet it.

++

Thanks Mike and Pascal, it makes a lot of sense indeed. this will save me many headaches in the future ;-)

rgds
wim