a 0.079" ∅ (near AWG12) heated poorly and slow but sturdy.

Mashing the tip into a shape then filing it to the final shape (reducing the amount of copper) made for a good sturdy tip with a finer (not a "Fine") point has served me well in those times when I needed to use the gun.
As I said before:

As for tips: I've made out of copper wire flattened tips for cutting plastic. Made special loop tips for scooping styrofoam out of a board leaving just a wire channel for other projects.

 

There is also a flat metal ribbon used for cutting synthetic rope. I still use my pocket knife and a lighter to seal the ends though as it's always handy in pocket instead of going in the house looking for a gun and extension cord. But it is very handy at the store for cutting off lengths of cordage and seals the end at the same time.