I achieved the fillet by changing the units from cm to mm, I find this a strange behavior, I wouldn't expect changing units would effect anything in MoI's calculations, if a sphere is 0.06cm in MoI and I change the units to mm isn't the sphere still the same size ?
I would think the fillet should work in any unit type, be it inch, ft, mm etc, I understand if you model something tiny weeny, but this particular example should have no problem no matter what unit type is used.

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