I have a part which I want to make wholly one solid. It has a curved lip on it, which is currently separate from the body. I made the lip using a loft, and had intended to follow the original edges of the part, but it wouldn't accept that particular geometry as guide curves, as the places where the lines separated themselves wasn't along the start/end points of the loft. There could be other issues with those for the operation, but I don't know of them. I converted the original two edges to 3d sketches with the convert entities command, and was able to make the lip from those, but I now face the issue of how to fuse that new piece to the other piece of the part. I tried using the combine tool on them, but it would say that it failed due to a geometric condition. I've seen a post about issues with someone having issues combining pieces of a part with variable fillets before, but I honestly didn't know how to interpret the information I saw there in terms of this particular model. If anyone had any ideas on how to resolve this issue, it would be appreciated. If anyone also knew anything as to whether it could be properly 3d printed even if it has two directly adjacent but not connected parts with slightly dissimilar geometry, that information would also be useful. I'd imagine that could cause some issues, but I honestly don't know.