I want to make a solid hemisphere. I found the way to do it by making to hemicycles and drawing two lines joining them (as seen on the picture). Then, when I revolved the sketch by 180 degrees I realised the hemisphere to be hollow!! I then tried to find a way to make it solid. I went back to the 2-D sketch and filled the surface (Insert->Surface->Fill) inside the hemisphere. I saw some lines (which I don't know exactly why they appeared inside the surface) and I noticed that the hemicircle had become more of polygon (not an exact circle). I was OK with that since the difference was not that visible when I zoomed out, but then I had a problem revolving the sketch. I want to revolve it around a centerline but you can see on the picture the error that pops out. Any help and explanations on the above matter would be much appreciated!!! (as I have to fill many parts now that I realised that they are all hollow!!!)
P.S. I found online a video on how to make a bowl. ( http://www.youtube.com/watch?v=FgH3C1HadvM ) But that procedure is way to long from where I am now, and I feel I'm close to making it solid!!