Changes

A support beam is required on ''every'' wall of a cave tile (both sides) to prevent the tile from collapsing. A [[reinforced tile wall]] can't be mined.

'''Hint:''' If making the a support beams beam outside of the mine cave, and using a [[small cart]] (or [[rowboat]]) to transport them, the best approach is to leave it the beam [[unfinished]] (e.g. requiring a shaft or a ribbon), and finish it inside the cave. Completed However, completed support beams ''will however '' fit in a [[large cart]].