A Discussion on The Fundamentals of Tree Felling

Kind of wish I’d gunned more to the camera’s right and avoided the cactus but there was a porch there. Mesquite is usually brittle but sometimes holds. If it had held, it might have gotten the porch.
 
When I started doing swing Dutchmen, my rule of thumb (adjust with experience and trees, I’m still learning) I would do my flat cut aimed between the lean and the lay and put only the undercut to the lay. Don’t trust em
 
  • Like
Reactions: Evo
davidwyby said:
When I started doing swing Dutchmen, my rule of thumb (adjust with experience and trees, I’m still learning) I would do my flat cut aimed between the lean and the lay and put only the undercut to the lay. Don’t trust em
Click to expand...
When the situation allows they can be great, unfortunately I don’t get that situation very often and use rope and wedges more often.
 
Correct me if I'm wrong. Most species that timber fellers do in the woods are chewy fiber, good hinge-ing. The most common reason to start the fell in one direction and then slightly change it's direction mid-fell is to get it's top/branches past/around a nearby tree while also placing it on the ground in a spot that is partially behind the in-the-way tree. One has to have extra confidence in the hinge holding to take the extra loading of changing the tree's trajectory mid swing.

That would be viable circumstances.

As the wood becomes less reliable with respect to hinge-ing (eg species, brittle, rotten, defect etc), you're just increasing the odds of hinge failure if you use it when there's other measures that can be taken. I guess it depends on the consequences of failure. Out in the woods, not so much to lose.
 
Bart_ said:
Correct me if I'm wrong. Most species that timber fellers do in the woods are chewy fiber, good hinge-ing. The most common reason to start the fell in one direction and then slightly change it's direction mid-fell is to get it's top/branches past/around a nearby tree while also placing it on the ground in a spot that is partially behind the in-the-way tree. One has to have extra confidence in the hinge holding to take the extra loading of changing the tree's trajectory mid swing.

That would be viable circumstances.

As the wood becomes less reliable with respect to hinge-ing (eg species, brittle, rotten, defect etc), you're just increasing the odds of hinge failure if you use it when there's other measures that can be taken. I guess it depends on the consequences of failure. Out in the woods, not so much to lose.
Click to expand...
That's not my impression. But can't say for sure. First of all we need to define our vocabulary. Doug Dent has a pretty wide range of cuts he called swing Dutchmans in the book on timber falling. He later stopped teaching those cuts because he found them too unreliable to teach... however, it's an important distinction thst just because they are too unreliable to teach does not mean they are too unreliable to use, by those that understand all the rekated variables that can effect outcomes. Too unreliable to teach just means there are too many variables to account for and thrn be able to explain in a teaching format.

I personally have used a version if the swing Dutchman with a traditional or open face, but mostly just to fight side lean while keeping the notch gunned to the lay. IMO you really need to be usinh it with a narrow Humboldt to get the tree to turn as it falls.

From the video's I've seen, that technique is mostly used to use the front lean of the tree to get it moving, and then it's easier to get it to turn once it starts moving thsn it would be to beat it to death with wedges, to get it to start moving sideways to the lean.

The one variable with which I've had enough experience to comment on is size... the swing Dutchman I use is much better suited to smaller diameter wood.. big heavy trees are much more likely to settle on the kerf when the lean side corner of the hinge is taken out. For anything with size, I gut the hinge, leaving just enough wood fiber on the lean side to keep it from getting crished by the side weight.
 
Last edited:
How many degrees off axis direction change is achieved using the cut? Pretty sure I've never seen 20 degrees, probably not even 10 degrees.

By off axis I mean initial landing spot vs course-changed landing spot. Like clock hands from the stump.

?


And how many degrees off vertical does the course correction kick in? This affects how much extra load is put on the hinge.
 
David, 90 degrees course change is like a football player running straight downfield and then abruptly bolting straight for the sideline. 180 is falling forward, stopping mid fall and reversing direction to fall backwards.

I think you're mistaken or have misinterpreted. 30 degrees on a clock face is 12:00 vs 1:00

Good vid. I saw about 20 deg course change looking to start at about 10 deg off vertical, all at very slow speed on a skinny pole with lots of wind/air drag at he top to keep the speed down. On a green chewy conifer. The closing portion of the notch looked like about 20 degrees which roughly matches the off-vertical jog-onset angle (which was hard to gauge accurately from the vid).
 
Last edited:
Bart_ said:
David, 90 degrees course change is like a football player running straight downfield and then abruptly bolting straight for the sideline. 180 is falling forward, stopping mid fall and reversing direction to fall backwards.

I think you're mistaken or have misinterpreted. 30 degrees on a clock face is 12:00 vs 1:00

Good vid. I saw about 20 deg course change looking to start at about 10 deg off vertical, all at very slow speed on a skinny pole with lots of wind/air drag at he top to keep the speed down. On a green chewy conifer. The closing portion of the notch looked like about 20 degrees which roughly matches the off-vertical jog-onset angle (which was hard to gauge accurately from the vid).
Click to expand...
I have done 12-3

Mitch 12-6, or very close
 
Looked like it went about 1 degree off vertical before changing course. ? Not much obstacle clearing capability. ?
 
100' x sin(1 deg) = 100' x 0.017 = 1.7 feet you'd have to watch the top just deflect a bit maybe beside another stationary top for reference. Maybe it's more like 2 deg or 3.5 feet motion. Rough numbers. 5 deg @100' = 8.7 feet. know the feet know the angle


Minor concept correction. If the stem fells a bit directly downfield then pulls a hard 90 deg left for the sideline, it's not going to end up laying pure 90 deg sideways, it'll be at a leftward vector which is the addition of the downfield plus the hard 90 left. Angles other than hard 90 left would add as vectors too. How much each one contributes depends on the kick-point (angle off vertical) when the spar direction changes. Someone want to do up the math? Could end up with a table of face opening angles vs change in lay. Maybe also "go around" clearance at a height on the tree. You'd have to use the table with common sense, not expecting miracle physics or miracle strength hinges.
 
Bart_ said:
100' x sin(1 deg) = 100' x 0.017 = 1.7 feet you'd have to watch the top just deflect a bit maybe beside another stationary top for reference. Maybe it's more like 2 deg or 3.5 feet motion. Rough numbers. 5 deg @100' = 8.7 feet. know the feet know the angle


Minor concept correction. If the stem fells a bit directly downfield then pulls a hard 90 deg left for the sideline, it's not going to end up laying pure 90 deg sideways, it'll be at a leftward vector which is the addition of the downfield plus the hard 90 left. Angles other than hard 90 left would add as vectors too. How much each one contributes depends on the kick-point (angle off vertical) when the spar direction changes. Someone want to do up the math? Could end up with a table of face opening angles vs change in lay. Maybe also "go around" clearance at a height on the tree. You'd have to use the table with common sense, not expecting miracle physics or miracle strength hinges.
Click to expand...
You might be over thinking this one... it's a little challenging to tell the lean of a tree from video alone, but those seem pretty clear to me that he got a lot of swing out of those cuts...
 
You must log in or register to reply here.

New threads New posts

Back
Top Bottom