Eaton Rapids Joe sent a link for a chainsaw story in the UK Daily Mail (click the link), and it is an educational article and video. Much of the information in the article is obviously wrong if you have spent any time on our chainsaw posts. Matt Charland, the man who is nearly killed, is no lumberjack, though he may have cut trees before. He said the tree had a weird angle, but the tree appears to have forward weight and it should have fallen right if he had made the proper cuts. The tree is dead, and that is one of the failure factors. Dead trees can be brittle and lose fiber strength. So, what did Mr. Charland do that was wrong?
You always should evaluate weight and lean on every tree you cut from two different angles, and assess whether the tree will need to be wedged, and if so, how much lift you need to provide. Wedging a dead back-weighted tree is risky because the hinge is likely to part when you lift with your wedges.
This screen shot at 36 seconds makes the tree appear to have forward weight, and the next one at 39. Click on the first photo and they will come up so you can click through them.seconds shows the tree tipped forward. Then the hinge fails. This is the real failure in the process. The hinge was obviously not strong enough, and probably was cut too thin. The back cut on any tree you fall should be perpendicular to the stem, which usually is a horizontal cut, not angled as this one is. Many novices cut on an angle, and the explanation they always give me is that it will make the stump push the tree over. At best, you cut through more wood to make the back cut. At worst, as in this case, the hinge failed, the tree slid on the sloping back cut, and the butt of the tree was propelled forward by about three feet, totally changing the balance of the tree, brittle wood was jarred loose from the treetop and rained down, and the tree which had started forward, changed direction and fell opposite of the planned direction.
Sliding
2 comments:
Thanks for posting this for a wider audience.
-Joe
Hey, Joe! I have seen many stumps like this one over the years, and it is good to see the consequences in action. Doing the screen shots and running them, you can see that the tree would have fallen in the desired direction if not for the sloping back cut and hinge failure. Thanks again for the link! David N
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