Hi osx59 - that's definitely going to be a difficult model to fillet, particularly around the very sharp concave type corner in the back side area.

I don't think that the edge-based filleter is going to figure out how to build a corner connection piece in that area, to fillet that you will have to do a lot more "low level" type surface modeling. I have attached a model here (ft2_2.zip) that shows the result of some of this, I trimmed some areas back and did a blend to try and make a smooth connection in that corner, and did some surface/surface fillets in a few places. Most of this was done by using Edit/Separate first to break the model into individual surfaces and then work on them.

I hope that might give you some ideas on how to make some progress at least, it will probably be a fairly difficult job.


Maybe it would be easier to get this finished by making one big single surface for the top piece and then cutting a hole for the kind of slot...

- Michael