Reply by TeamTurpin

How “perfect” does the inside hole need to be? If it doesn’t have to be a perfect cylinder, what about boring a circular series of 1” holes with a long twist bit? Once you have the holes bored, you could use a long slender bladed saw to connect the holes (like a long keyhole saw or any thin saw with a blade that can be removed and reconnected inside the log—like a tree branch saw). It would leave a jagged interior, but you could clean up the ends of the log with a sharp chisel. Just thinking out loud.

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