I am currently working with a surface model that was giving me fits while trying to use the Solidworks fillet feature. It would not successfully propagate through all the faces that I needed a fillet between. So I changed my POV on the situation and came up with an idea that I thought was pretty slick to avoid the mess of the fillet feature. I trimmed the two faces back and then created a boundary surface that had the right contour between the two faces, effectively creating a constant length fillet. This seemed to work beautifully through my part. Now for the issues... I am having to offset the original part and thicken it (using thicken feature and other methods such as offset + lofting to form solid). Then I have to offset from the thickened face. This is where the problems start to show up.
For some reason, my "fillet" splits into two separate faces after enough offsetting/thickening. For instance, there is a forward and an aft section to the fillet (roughly parallel to the faces needing the fillet). This is fine for the thickened feature, but it is causing other issues down the road. What are some ways that I can make my "fillet" more robust? After an extreme enough distance, the fillet actually breaks down an leaves a gap between the original two surfaces. Is there anything I can do to improve this without creating more surfaces to fill the gaps?