Hi Brandroid, yes the fillet engine in the geometry library that MoI uses has a lot of trouble with this type of "disappearing fillet" type case where one side not only converges together but also is converging to a shared tangent area.

My best advice is to get ViaCAD to help out with these kinds of fillets, its fillet engine tends to handle this stuff much better. Export your model out to an SAT file, then import it into ViaCAD, and then bring it back into MoI. ViaCAD is available for $99: http://www.punchcad.com/p-9-viacad-2d3d-v8.aspx .

That would certainly be the easiest and most time effective method.


A couple of things that might help in MoI - the scale of the object is getting kind of small, that can be problematic when pieces that need to be generated are particularly small in size, say less than about 0.05 units or so, and also I'm not sure if the 2 halves of your object are fully smooth where they meet up, when you have 2 surfaces coming together which approach pretty closely to being tangent to one another but are actually about 3 to 5 degrees or so off from tangent that tends to make for filleting difficulties as well since it tends to require little slivery juncture pieces between fillet segments. Fillet surfaces only naturally join up end-to-end along fully smooth edges.

You've also got an area that's got a tight bend in the surface already, sometimes things like that can tend to be better to leave as sharp edges initially and then use filleting to round them off as well rather, you may be far enough away from that area right now, but trying to put an additional fillet that has to turn around a tight bend can also be problematic as well.

Those are some general tips, but I would really recommend seeing if you can just import into ViaCAD and get your fillet job done there and then bring it back into MoI.

- Michael