Damage scaling of augments is 1d6 per four levels. Cannith Crafting falls behind so that at level 20 it is 4d6 not 6d6.
I think they should be made equal, don’t you?
CC scaling: https://ddowiki.com/page/Cannith_Crafting/table_3b
Augment scaling: https://ddowiki.com/page/Augment_Slot#Augment_Slot