Closed reculated shell structure (dome)

hello !!

am beginner in grasshopper, currently am working on a shell structure (dome),
first, i have defined a ‘nurbs curve’ and then ‘rail revolution’ and then quad panel with subdivisions in order to set ribbed dome .but i have found that the beams has not the same length (not symmetrical) . the problem might be because of the rail revolution and the curve (as mentioned in the figure) .
is there anyone who can help me to figure out the solution, please!!