The stated size of a bandsaw is the dimension from the blade to the support column. The capacity of the machine depends on the maximum height the upper blade guide can be raised above the table. That's also the resaw capacity.
Whether a machine will be able to cut that dimension in hardwood depends on the blade, it's condition and the HP of the motor. A 10" or 9" machine will have about a 1/3HP motor. That will be adequate for hobby work, cutting 1" and slightly thicker material, but will not be adequate for resawing 4"- 6" thick hardwood in my experience. I have a nice 10" Craftsman with the 1/3 HP motor, which I bought for my son who was 8 years old to learn on and to use. I have since taken it over as a utility machine to cut various materials like plexiglas, foam rubber and smaller wood pieces. I use the larger bandsaws I have which are set up for resawing thicker materials up to 8". These are 14" and 18" saws and have up to 3 HP motors. Having more than one bandsaw saves the time of changing over the blades for specific operations, a big factor in my shop. You must "adjust" the side guides and rear guide when changing blade thicknesses and widths, a PITA depending.
The answer to your question will only be as detailed and specific as the question is detailed and specific. Good questions also include a sketch or a photo that illustrates your issue. (:< D)
Last edited by woodnthings; 10-14-2012 at 11:08 AM.
Reason: wording: from change to adjust