The large furnace and refinery don't have a held item durability which is why they don't take damage. There is no logical way of persistence without using a custom class which isn't efficient.
The wood farming is known and I've kind of brushed it off since it's not really a good method to get wood. You can hit a tree once to get the same amount of wood from placing and remove 2-3 ovens. Though, since I'm already under the hood I'll get that squared away.