Table to hold circuiromt board for homebuilt cnc mill/drill/router

Hello everyone,
I am assembling a homebuilt too to make circuit boards from old printers,
and am looking for ideas to make a small easy table to hold them, I will be
wanting to do double sided boards, so some way of being able to keep
alingment when turning them over would be good,
i only expect to be making 4x6 boards as that is the limitation of the free
eagle cad.

Any suggestions would be very helpful


Al WB0YRQ