Why do logs check(crack)?
First of all, it should be noted that just because every log cracks, it does not mean that every sculpture will crack. The reasons for this, and the steps I have taken to help keep my sculptures from cracking will be explained in further detail in the next question and answer. Now to answer why logs crack: Every tree has moisture (sap and water) in it. This is how the tree stays alive. And since logs are from trees, they have moisture as well. The majority of cracking occurs as the log dries out. The outside of the log (sapwood) shrinks as moisture leaves the wood fibers. The outside of the log dries much faster than the inside (heartwood). If both the inside and the outside of the log dried as one unit, at the same speed, it wood shrink evenly and no cracking would occur. Therefore as the outside dries out faster and shrinks it cracks around the log. Also, wood expands and contracts with the changes in humidity in the air. If it is very humid, wood can swell slightly, and if it is dry
