one hanger variable i have not seen much discussed on the forum is the distance from the centre of the axle slot in the dropout to the center of the hanger hole/tab.

on campag and on the copyolo dropouts this dimension is about 26mm. on most asian hanger plates and some asian dropouts this dimension is about 32mm. some home builders get a surprise when they attempt to get their maeda touring mechs rated at 34t to handle that size cog when fitted to a campag dimension dropout as happened to member LucasT-603 on his allegro build -

http://www.bikeforums.net/classic-vi...storation.html