Stopping a Wandering Band Saw Blade
How can I make a band saw blade cut in a straight line? Regardless of what size blade I use or the thickness of the material I'm cutting, the blade wanders off course. I've given up trying to resaw with it because, even with a jig and 3/4 inch blade (the widest my saw will take), I can't cut pieces with a consistent thickness. I replaced the guide blocks and adjusted everything that has a screw in it, but I couldn't solve the problem. - Bob Bacon
Tim Inman: Because band saw blades ride on crowned wheels, they always have a little "camber" angle relative to the vertical axis of the wheel. This causes the blade to tip a little and makes the cut "pull" to the side. Even if you get it "just right," the rubber tires on the wheels will likely change over time, and the camber angle will change with it, throwing your careful adjustments off.
You can use a simple shop-made guide (a scrap of wood) that provides a single pressure point right at the edge of the cutting teeth on your blade. You can set this for the thickness of the cut. Then, what I do is very low-tech, but very effective. Draw a pencil line down the edge of the board where you want the cut. Set the guide, and follow the line with your eye. The guide allows you to pivot the board as needed to keep the cut going right down the line - and no fence binding or trouble to worry over. I use this system all the time, and it makes resawing or long cuts a joy, instead of a pain. The blades are less likely to break, too.
Chris Marshall: A point fence works wonders! My band saw's rip fence can also be adjusted for front-to-back blade drift, and I've actually had good luck using it for resawing once I adjust for the saw's drift that day (as Tim says, it changes with blade sharpness, tire wear and so forth).