You can either ask an Artisan to do it or talk to one of the following NPCs: * (Weapon Craftsman) Mairath (Breezy Hills) * (Smith) Patrick (Magic City of the Eucar) * (Smith) Nel Eldora (Xita Refuge) Materials needed: The higher the quality of the chemicals you use the higher the increase in durability per refine (Maximum: Durability=120)