The other thing again, similar but different; planes of failure. Pretty much the same idea, but this piece: tangential, radial, longitudinal. If I just felt like getting violent splits very easily on a tangential surface. Similar but different: Splits splits very easily on your radial surface. These would if we were splitting firewood, this is the direction we would be splitting because we can. If we were to then try to do the same thing across the longitudinal direction, which would be the length of the log, or the length of the tree, you can sit here and bang on this all day. You're not going to cut it or split it. This is the direction where you use your chainsaw, because you have to. You're not going, there's no way you're gonna. Ah, you might get through that someday, but not anytime soon, so again just something to keep in mind when when you're building things or destroying things. The orientation of your piece of wood: very important. about ninety to ninety-five percent of the problems i run into in terms of wood utilization are related to moisture. Either moisture gain, moisture loss, which results in shrinkage and swelling. If we cannot manage that, our whatever we built; our piece of furniture, or our homes, or our nice hardwood flooring: bad things are going to happen, and so again because the wood anatomy is different in all three directions, the shrinkage and swelling are different in all three directions and I'm just going to try to illustrate that. Longitudinal direction. In normal wood, shrinkage and swelling is virtually negligible. It's not enough to worry about. Tangential direction; Shrinkage and swelling are the greatest, and in a radial direction shrinkage and swelling are generally less than tangential, so I've picked the worst surface. This is just a thin sheet of veneer. Like we would use for furniture construction. When veneer is made; at least these, were just sliced off the log. So it's actually a combination of tangential and radial, but the center; mostly tangential. If I wet; get one surface wet; leave the other one dry, even on something this thin, the wet surface will shrink, or the wet surface will swell. The dry surface is going to try to resist that swelling and it's not going to be pretty. So just that quick, and notice it's shrinking, oops, swelling tangentially. Nothing's happening longitudinal direction you basically we can ignore the longitudinal shrinkage or swelling in most cases. So anytime you got wood flooring or furniture or your two-by-fours are sitting outside in the rain at the building supply store, wood's trying to adjust to the change in moisture content. Even on the surface, it's building up some interesting stresses in there, and things are going to happen. There you go. So, because this piece was very thin, it was free to move. This doesn't always happen in a, in a thicker piece of wood. But, ah... ...that's still tightening up. The next trick is what happens as we remove the moisture. Now, we're just gonna hit this with a blow dryer. It should flatten out. Become very close to it. * Silent time-lapse of blow drying the veneer * Just a little bit of effort, a little bit of time, a little bit of heat, and air movement. We've returned this piece, very close to it's, to where we started in terms of flatness. We could do a little better, if we were a little more careful. That's how quickly things can change in wood when exposed to moisture. These are forces that we have to deal with, whenever we're drying lumber, or trying to protect it from moisture in the environment. So, what this means in the real world is the difference between having a decent straight nice piece of wood to work with, or not. This is this is not even the worst piece i have laying around but it was the one I could find. If you do not manage the the drying or the rewetting of wood, really bad things are going to happen. So to further complicate the drying issue, what we have here is the possible addition of juvenile wood and what that is, is here you have more mature wood. Here's the bark the outside of the tree. Here you have the Rings getting smaller in here, so you have the center of the tree somewhere about here. So you would have juvenile wood on this side, more mature wood on this side, and in juvenile wood, the longitudinal shrinkage is much more than normal wood, and as such, you end up with a cupped board like this, and whether this could have been saved by a better drying process, because of all the knots? But you can look at this one, and you can see this is similar, in that here you have the pith somewhere in here. The center of the tree, somewhere in here. More mature wood, but this has been dried specifically to relieve stresses as you go, and end up with a nice straight piece of lumber.
