i know there has been a lot said on imcs values here before, but this is strange,

i cut a 460 const curve imcs 25 c30 NP down to 427 to try it on some smaller sails unfortunately have't had much sailing time/wind to try it out, but calculated the imcs(out of curiosity) according to the fibrespar website and came up with 23 for the shorter version, I would have thought it would stay the same or be stiffer because it is shorter.

Also have a 445 NP const curve imcs 25 and did the calcs and got imcs 21

both masts are 2nd hand, so the only thing i can come up with is that the tops do not match the bottoms.

any thoughts