Originally Posted by
FlatFender
Um, If I were hypothetically building two identical wheels, except that one had a double wall rim, and one had a single wall rim, but both rims have the same ERD, ....
...If the spokes are sticking out of the top of the nipple 5mm, there is a problem. The spokes are too long, and the nipples dont have many threads left to grasp on the spoke.
Yes, if the ERD is the same then yes they would use the same spokes. But generally the sections used for double wall rims will have a smaller ERD than single wall rims just due to their design since the outermost wall will be pretty close to the single wall center and the second part of the double wall has to be located further inwards to form the cavity between the two walls.
In fact since his wheel has the spokes sticking up generally to the lower portion of the outer center trough I'd be willing to put money on the idea that a previous owner had a single wall rim on there and it got damaged and so he bodged on this double wall using the original spokes and that's why they are sticking out so far from the nipple ends but only up to the outer wall which is roughly where the single wall rim would have been.