See how to refurbish a 215 gram Japanese plane adjusting hammer using only hand tools to make the handle. I try an experiment refurbishing the hammer head by seasoning it like you would cast iron. I won this hammer on Ebay. Only thing is the hammer head had a little rust on it and the handle easily slips out of the hammer head. I spent a little time over the last couple weekends working on making a new hammer handle from a small log of olive wood. The tool maker’s name inscribed on the bottom is Yama.