The best material for a router table top is 3/4" baltic birch plywood. This should be covered both sides with a high pressure laminate like Formica or Laminex. This top will be very strong, light weight, and easy to work with. The router workshop table top is made this way, and you can purchse just the table top and mount it to your own base. This gives you the advantage of a high quality phenolic plastic plate which will fit your router.
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