I needed to make some drawers for a coffee table and thought this was the perfect opportunity to use my new dado set. I have an Avenger 8" 42T dado set that I received for my birthday. I made a 1/4 inch finger joint jig and went to town. When I finished I noticed the saw blades did not leave a square dado but it's rounded. I went back with a 1/4" morticing chisel and cleaned them up but that didn't come out as clean as I would have liked. Is this a common problem or just a cheap dado set? Thanks for your help.