don't use the 10" dado
They don't want you to use it, it will have too much spinning inertia and may damage the motor/arbor.
A single blade on the table saw will define the outsides of the cut and you can "waste" away the interior by several means ...jigsaw, handsaw, bandsaw, multiple table saw cuts... etc.
I have a 10" dado for my 12" tablesaw, it's a monster and very intimidating when spinning at 5,000 RPMs.
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; 11-23-2014 at 01:47 PM.