Department of Labor Seal photos representing the workforce - digital imageryŠ copyright 2001 photodisc, inc.
Department of Labor Seal www.osha.gov   [skip navigational links] Search    Advanced Search | A-Z Index
Home
Standards
Glossary
User Guide
The Humbolt Bottom or Undercut
The undercut is the second of two cuts that result in a Humbolt notch. The notch is made on the side of the tree facing the direction that you want it to fall.
The Correct Cut
1. Starting Point
Very Important — begin below the top cut at the level that will create at least a 45 degree notch opening
2. Angle of Attack
Important — cut upward at a 45 degree angle
3. Ending Point
Very important — stop when the cut reaches the end point of the face cut. Ideally, you have created a 45 degree notch opening.
Diagram of correct cut
cross-section
A Common Incorrect Cut
red arrow
Commom incorrect cut
Here the ending point of the under cut doesn't meet the endpoint of the first cut . . .
. . . resulting in a Dutchman notch.
 
Continue with the Humbolt Notch Click on Arrow to Continue with Lesson 4

Return to the Cuts page
 
Back to Top Back to Top www.osha.gov www.dol.gov

Contact Us | Freedom of Information Act | Customer Survey
Privacy and Security Statement | Disclaimers
Occupational Safety & Health Administration
200 Constitution Avenue, NW
Washington, DC 20210