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Safety and Health Topics > Multimedia > Logging Slide Presentation > Slide 63

Logging Slide Presentation   63 of 82  Back    Next    Index    Kinds of Notches Open-faced Notch Click here to learn how to cut an Open-faced Notch Conventional Notch Click here to learn how to cut a Conventional Notch Humbolt Notch Click here to learn how to cut a Humbolt Notch Total angle ideally 90 degrees; at least 70 degrees 45 degrees 45 degrees Top Cut angled downward 70 degrees angled downward 45 degrees flat horizontal Bottom Cut angled upward 20 degrees flat horizontal angled upward 45 degrees Back Cut horizontal; at the same height as the corner of the notch horizontal; at least 1 inch above the bottom cut horizontal; at least 1 inch above the top cut Depth 1/4 - 1/3 of tree diameter 1/4 - 1/3 of tree diameter 1/4 - 1/3 of tree diameter Point of notch closure just before tree hits ground middle of fall middle of fall Degree of safety high medium medium Advantages greater accuracy of felling into target area hinge stays intact until tree hits ground less danger of kickback and other out-of-control movement familiar to many loggers saves slightly more wood familiar to many loggers Disadvantages hinge may have to be cut off hinge breaks early hinge breaks early While all three of these notches are acceptable, the Open-faced Notch is clearly the safest and most accurate.

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