Not sure. Depends on how thick the wood is and how dry you want it. Green wood will lose alot of weight even in the 72% basement, and needs to before going into the box. So I rough out a couple of those somewhat dry staves and put them in the box for at least a couple of weeks while I'm working some other bow. When I finally get one of those to floor tiller I stop and put it back in the box for at least 24 hours. When I actually start tillering I can "feel" how dry the wood is when I'm working it--by the dryness of the chips and the springiness of the wood. It might not be a perfect system but its alot better than what I was doing.