So, I'm attempting to draw an arc on the outside of a cylinder, but since SU makes both the arcs and cylinder out of lines, the two do not match up and some of the arc is outside, some inside, of the body of my cylinder. Is there a fix for this or just some way with which I am not familiar?

Thanks

So, I've done some basic SU work, but now I'm designing a building for an abandoned lot (it's destined to be a parking lot) as a part of my architecture apprenticeship. So, I opted with a circular building with a curved top and circular hole in the center for more natural light, but drawing the top has stumped me. Can anyone point me to a tutorial online or give me directions to make this arc solid?

Thanks,
redsox985