Graham Oakes replies: Burls can be very difficult to divide into sections. The reason for this is that no two burls are alike. Some burls are a lump on the side of the tree, and others wrap all the way around the tree and these are the kind that give the most problems. The key to dividing a burl into sections is to keep two things in mind.
First is that you cannot have the pith of the tree in your finished bowl, unless the burl is completely dry, which takes a very long time. The second is that you never know what you are going to find on the inside of the burl. Taking apart the burl requires a person to visualize where the bowl is inside the burl and then make cuts to extract the piece.
Something I have noticed about burls is that most have natural veins running through the wood that help a person decide where to cut. When I cut a burl, I strictly follow these veins which can usually be seen on the surface of the bark.
One mistake many people make when trying to turn large burl bowls is they cut the burl directly in half sideways and turn a large bowl that has the pith of the tree running through it. This kind of bowl looks great but it most likely will crack badly because of the pith in the wood. Your bowls will come out much better if the burl is cut lengthwise thus eliminating the pith.
Another point to remember is that burl wood is highly reactive and can crack, split and warp in a matter of seconds. When people ask me about turning burl, I tell them two things – don’t get discouraged and just keep turning. Happy turning.