My friends and I were wondering how weapon damage die work for small/medium/large weapons (ie a medium weapon having 2d10 damage) one of the questions being can a medium weapon do 2d10 damage while not being colossal or something.
The other question would be how could one go around crafting these types of weapons and if they could be upgraded to have enhancements etc...
As far as weapon damage goes there is a chart. I don't remember where in the book it is though.
But the short answer is you cannot do any of what you want to do without the dim saying you can do it. Your wanting to go outside the general guidelines of these things.
There are spells which increase weapon size temporarily like lead blades. Enlarge person etc.