I know it has a lot to do with heat and humidity. But about how long does it take before the bees capped the cured honey?
no telling. More bees, faster capping. They will cap it when its ready and not sooner!
Good ventilation in the hives seem to help too but I don't have anything solid to compare the results to. Just seems that way.
Like so many things of the hive . . . they cap when it meets their purposes. They seem to have, among so many other skills and tools, a built in refractometer that rings when the nectar is 18% or less (usually less) moisture content honey. Ventilation is very helpfull! I give them plenty in the stack of supers.