Although not required for coordinate clues, a watch can be used with a sextant and a chart in the inventory to find the coordinates.
After first obtaining a watch from Brother Kojo, the player may thereafter make watches with level 28 Crafting or higher. A watch can be made by having one steel bar and one clockwork in the inventory and clicking on a crafting table 4 at the Workshop of a player's house. Making a watch will give 15 Crafting experience.