Hi Steve,

I had a shot at this one and it's a dog! I think the combination of the surfaces you've got there has MoI filleting stumped, there are some situations where the filleting in the library used for MoI falls over, MoI users are aware of this and in some situations they would bring their model into another more mature modeling program to do these sort of bits, one day I do believe that the library MoI uses will be able to do your fillet with ease, it's just that we have to be patient and use other tools in conjunction with MoI which is a normal thing with all software, we can't have one tool that does everything.

I did manage to get some success when changing the units to millimetres, but it would still mean some low level modeling involving separating and trimming surfaces. Sometimes reconstructing the surfaces differently can help, like using sweep instead of loft where the slightly different structure of the surface could be more friendly for the other commands, but that's more on an experimental level to get to know your software better.....I know, most of us just want the job done, unfortunately it's not a perfect world in software land :)

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