I'm sure I'm doing something wrong, but does anyone know why my groove disappears in a Lip/Groove situation? For simplicity, I Isolate the two parts, then I edit one of the parts in an assemly. Insert the Fastening Feature, and I get a nice lip on one part, and a groove on the other part.
Then, after a while I'll be working on the parts, and the groove disappears! It seems that when I add more features down the design tree, something makes it go away. I can't say if it's only the groove, I may have lost the lip at some point.