Nov. 02, 09 - 10:05PM
You're experiencing drift, which happens when a bandsaw blade and fence are not parallel to each other. Until you "get the drift," you'll continue to experience this problem.
Unlike a table saw, on which you can set the parallelism between the blade and fence once and be done, you need to check it on your band saw each time you change blades. This is, in part, due to the the tension applied to a band saw blade to keep it on the saw.
Most band saw fences allow the user to change the angle of the fence relative to the blade. If your material is pulling away from the fence as you cut, try loosening the fence and angling it more toward the blade. If you angle it too far toward the blade you'll begin to bind the material between the blade and fence, and will need to slightly change the angle so the fence is angled more away from the blade.
George Vondriska, Editor