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I have a big slab which is a cross section of a large tree trunk. The slab is about 10 inches thick and 3 feet in diameter, so it is large, heavy piece of wood. I cannot lift it. I moved to its current location by walking it. It took two men to load it into the car.
I want to smooth the top perfectly flat. The problem is that it is very rough cut and there are gashes by the chain saw. Trying to use a rasp to even it out would take forever.
Therefore I am thinking maybe to use a router. The problem is that I would need some kind of rail system to keep the router moving in a level plane over the surface. Also, what kind of bit would be used for doing something like this? Is there a better approach than using a router? If a router should be used, how can I move it X-Y and keep Z constant over a large surface?