Flat wooden surfaces are exposed to rotting caused by weather conditions. To extend their durability, and at the same time give a better look, you can posts, e.g. fences, and equip with sheet metal casings in the form of a shallow box. The shape of the shields should be exactly matched to the post cross-section yes, so that they can be pulled tightly over the forehead, no play. The casing can be glued with glue.
