Quote:
Originally Posted by Ekka  Hang on, what difference does the angle back cut make then if it still has to pivot?
Are you saying that some how it prevents the saw bar getting jammed from the tree sitting on it? |
I'd have to agree with newguy on this. We do this all the time and it does work. It's just a case of simple mathematics. Whe the surface of the cut is angled, it is bigger and has more square inches. So the pressure per square inch is less then if the cut was horizontal. We also use it on tops, ekka, because indeed, like newguy says, it keeps the top from sliding away on the back side where the climber is. Tests have shown that 1200 kg per square centimeter is needed to pull a hinge on a oak tree apart in the vertical direction. So if the cut is angled the pulling force on the wood is much less then if it where horizontal and will therefore less easily break apart in the wrong direction. If a top of a pine gets hung up when falling down, you actually could saw through the hinge and the top would still slide off of the cut in the right direction. When using this on hung up tops, you do have to realize that sometimes the upper branches of the top come back to the tree you're working on when falling down.We've been using this technique hundreds of times, it does work, but one has the know the math and the mechanics of it before using it.