Hi Martin, so trimming those marked areas should not be a problem you can do the trim at any point I would think.

re: filleting - you will definitely have significant problems filleting the areas that you show there with this kind of fragmented "lots of separate sub patch" type modeling technique.

It's difficult in general for the filleter to handle cases where 2 surfaces come together at only a slight crease where they are like within 5 to 10 degrees of being smooth with one another but not actually totally smooth. That kind of only slight sharpness usually means that the fillets that would be generated are very small in size particularly in corner juncture areas where multiple fillets are colliding together. The whole process of intersecting and cutting back fillets that meet at a juncture point tends to get confused when shallow angle corners since the fillets are close to having overlapping surface areas instead of having a sharp intersection line between them, and it also causes problems when the corner patch itself is extremely thin or slivery.

Also having more complex topology with multiple edges coming together at one juncture point also makes it hard for the corner aptch to be generated, so like for example this area here in your model is unlikely to be filletable:



Also areas like this where you only want to smooth some edges and not all of them can also make it difficult for the area at the juncture to be fillable:



Usually the best way to generate smoothness in areas like that is to build them out of larger surfaces instead of using fragmented sub patches. You can also build a surface to be extended and broader than you actually need the final result to be and then trim away some parts of it - it can often be easier to shape a more simplified 4-sided extended surface rather than trying to build surfaces that all directly hug every outline of your final result.

Also although you mentioned you don't like Blend , it may be better route for connecting up some areas of a model like this rather than fillet.

You're basically into an area of quite advanced surface modeling doing this kind of stuff, and there are some kinds of advanced surfacing tools that MoI simply does not have yet, like a "MatchSrf" tool for editing one surface to make it smooth to another one at an untrimmed edge. You may get good results taking your model into Rhino and using Rhino's MatchSrf or Patch tools to edit some areas of the model to make some smoother areas.

I do plan on working on adding more of these advanced surfacing tools in MoI v3 but for now using Rhino alongside of MoI may be your best bet for doing advanced surface "trim and patch" type modeling.

- Michael