Bandsaw blades are square on the back edge. While this is fine most of the time, if you are trying to cut tight curves the square back on the blade will catch more easily. This will result in a cut that is "jerky" and less smooth. To improve the smoothness of your curved cuts on the bandsaw, a simple trick is to curve the back of the blade. You can do this by running the saw and holding a sharpening stone against the back of the blade to round off the corners. Of course to be safe, make sure the stone is flat on the table of the saw and attach the stone to a piece of wood or some other scrap material so that you can keep your hands well away from the blade. But assuming you can do it safely, this simple trick really helps improve the smoothness of curves cut on the bandsaw.