The practice knot I carved when I started this project has a rounded look, like rope, but I tried something different with the final cross. Instead of creating rounded edges, they're chamfered, and I think it looks a lot nicer. (It's also a faster and easier technique.)
I used a gouge to chamfer the inside curves and cleaned
them up with a small round file. All straight edges and outside curves were chamfered with a straight chisel.Just another option if you plan to try this type of carving.