Trying to round out as many edges as I can on this little guy…getting some good results with FilletEdge on some of the edges and not so great on others…What would you do? Started rounded in the first place before joining all the surfaces?
check your open polysurface with _showEdges to find problems and holes.
_mergeAllCoPlanarFaces will help - before fillet
try to build surfaces in one piece if possible - not just mirror / copy them
when filletEge fails, there is _filletSrf to build single Surfaces and solve issues manually.
I also recommend to fix the basic surfaces first. Here is the basic model before filleting, after I cleaned it as much as I can: Model rough.3dm (612.9 KB) Model rough za SW.stp (90.9 KB)
Then I called a buddy of mine and he did this on Solidworks for you: Model rough ot SW.STEP (723.6 KB)