I'm modeling a bone and am trying to make one of the "wings" at the top of the bone lower than the rest of the bone. I'm attempting this by using a surface cut to chop off the top half, but keep getting the "operation failed due to geometric condition" error. I saw elsewhere that this typically happens when your cut would leave a very small section of essentially zero thickness, but I can't seem to find a spot that would be causing the issue. I'm trying to make an upward cut with Surface-Loft10. Any suggestions?