I was starting to use a tongue and groove cabinemaking set to unite some plywood to an anticipated maple face frame. I guess I just wasn't thinking. I just happened to have the plywood base cut first and decided to put a groove on the top at the sides of the base so that the plywood sides would be anchored securely and additionally help me align them (plus a couple pocket screws). When I ran the top sides of the plywood base across the groove cutting router bit of course I had a tremendous amount of tearout along the entire length of the groove. Will that only work on the ends? Is there any way to cut a dado like groove on the face of plywood without the tearout? Tape it? Is taping OK to do with a router bit? Or is a redesign in order?