Ok.. It was the chipper tooth that cleans out between the nibbler tooth.. they were not seated properly..?
David Best and I both agree that Felder really needs to up their game on their technical data with their product and at least give us some form of owners manual or instructions.. Once those chippers were all set correctly, the dado cut perfectly in melamine.? What we did was placed 2 boards of melamine ( you can use any very flat surface but the blade needs to be elevated so the teeth sit flat against the board, then loosen the allen head screws used to set the chipper tooth and make sure it's flat and then re tighten the set screw. It's very hard to see if they are out of alignment just by looking at them, but if you look closely, you can see where the back end of the tooth has hit the groove. That's all it takes because the back of the tooth is exiting the cut, pulling the fibers of the wood outward, causing the chip-out.? Hope this helps anyone having issues with these blades..