I had a large oak tree cut down in 2005 and had them cut the trunk into 6-foot sections, planning to cut each into 18-inch quarters for splitting into firewood. In retrospect, it would have been better to have them cut up the trunk but it's too late now.

I've whittled away at the branches over the years and finally got around to the trunk segments. These are about three feet in diameter at the bottom and end up about two feet in diameter at the other end. I've cut a few segments and split them, but this stuff is tough! The wood stayed hard in the center, didn't decay, probably because of the thickness, and when I hit the heart wood, it dulls my chain real quick.

The largest segment has three partial cuts around the circumference, but the parts are still joined in the center. I was thinking of pouring water into the groove that I've already cut in hopes that it might soften the core. Any other ideas?

Paul