Thanks for the idea. I made some progress resolving my flatness problem.
First, I realized I was testing flatness wrong. If I place the straightedges across the middle of the table I see the same small gap on either side. This looks more like a slight crown than a warped plate.
Second, I used some tape and shimmed up one side of the insert ring so no more catches.
However, the insert ring is not flat. It slopes inward quite a bit. So I'm looking at getting a replacement.
Finally, one of the mounting holes was drilled slightly off and when I tightened the screws down hard I heard a small "snap" and noticed plate had bowed. I elongated the errant hole and did not tighten that screw too hard. This time, the router plate did not deform.
Last edited by jmoore65; 07-10-2011 at 08:52 PM.