Best facecut for negative rigging?

I'd love to see the math on that.

The force of a facecut closing doesn't alter because the face cut is upside down.

Just like we can't negate gravity by walking on our hands.

Pity, really, because that would just be so cool.

I've studied slow motion video in some detail and feel pretty secure in saying that the Humboldt separates much faster then the traditional... Hinge breaks faster. I haven't figured out exactly how the physics works, but it makes sense that the humboldt would pry the hinge up more than a traditional, which also seems to have more push back on the stump in falling scenarios
 
Maybe .. just maybe the humboldt puts all the force on the hinge at once and causes it to pop, where the traditional starts ripping the fibers apart from back to front, which takes a bit more time.. FASCINATING!
 
the inclined plane of the top cut on traditional causes the stick to want to slide right back off the stump, where the inclined plane on the humboldt causes the top to want to slide down and forward.. that's clearly going to make a difference in the forces at the stump/cut... so some of the force of the top goes into push back on a traditional.. There is already going to be a tendency for the fibers in the back of the hinge to pull out first, because they have farther to go.. the push back might just exaggerate that effect, whereas the forward sliding motion of the Humboldt would counter act that effect. Causing the force to be spread more evenly across the entire hinge and make it pop all at once. Wonder where Kenny is on this ????
 
So, to simplify things, a standard furry top off a stripped stem.

A Humbolt is better than a standard to reduce the ?tooth smashing/rib breaking/ flying off the top scenario?

Is that a generally accepted thing?




I'd say sure. Just how a humboldt slides off the stump easier at ground level, the same thing happens up in the air. And if you 'chase it' once it's committed. The butt just slides off down the ramp. No flat ledge to sit, hit, or hang up on.
 
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I always thought that the conventional cut pushed back less because most of the force was straight down on the stem, as in a compression force more so than a sideways force that a Humboldt would exert. With a shallowish face notch the only force that the hinge would exert would be the tearing of the fibers, and since it would happen early on the fall, there would be minimal push back. Then i thought the Humboldt was handy if the top was possibly going to hit another tree or something, so the butt would kick down rather than back?
 
Cut the humboldt hinge off or nearly once it's committed and IMO it slides off the smoothest. also always seemed the best for landing conifer tops flat. Maybe just what I was used to? Only ever took any nasty rides when rigging a top and that was always attributed to to much friction. Never recall an issue cutting one and letting it sail.
 
Then i thought the Humboldt was handy if the top was possibly going to hit another tree or something, so the butt would kick down rather than back?

Anyone that's had a top hit another tree/limb, slide back over the cut and land in their lap will quickly learn the value of a humboldt when taking out tops.. If it looks lie the top is going to hang up, I cut the humboldt narrow and super steep (facing almost straight down), then push the stuck piece off the stump..

Here's a humboldt at 2:45 which hangs up and gets kicked off... If it had been steeper, it may not have needed to be kicked ...

Also at 6:00 there is another big top which holds up for a couple seconds as it brushed another tree.. The humboldt keeps it from coming back at me, which was good because this one was big enough to have get me in trouble if it had come back over the cut at me. It actually went earlier than planned because the pull line had too much pre-tension. I had left the stub on the left side as a blocker and was planning on moving over to that side before calling for the pull... It went early and thankfully the humboldt kept it off me. And you can clearly see on the slow motion that the but wanted to come back at me...

Also at 7:10 you'll see a head-high notchless falling cut, which hits the target perfectly after I walk away... but that conversation belongs on another thread...
<iframe width="560" height="315" src="https://www.youtube.com/embed/lWRoASX9Q4c?start=160" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
https://youtu.be/lWRoASX9Q4c?t=2m44s
 
For sure, need more Kenny on this one!
I think Kenny is slammed busy right now -- haven't seen him check in here for a couple of months. I checked out his site and Facebook page -- he is showing all the signs of being swamped with work, and says he's hiring to accommodate the workload.
 
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Murphy, I never thought I'd hear the Humboldt being promoted from the east coast! I can't imagine feeling as good about an inch or two of stump shot on a conventional in that situation.
A couple questions for you... why the vertical speedline on the last cut? And, if you were doing that same job tomorrow, would you make those same cuts?
Thanks for the update forestkeeper, reading Kenny's posts has become a real hobby of mine. I do pretty good these days, but he always loses me on the last paragraph.
 
Then you are generally ahead of me re Kenny's posts, Brock. I'm usually lost far earlier than that :).

Not to say that working at interpretation is wasted time...far from it.
 
Fk, they are talking about treespyder, who is also named Kenny. He's a walking encylopedia of tree work, and has studied rigging from sailing and other trades to become one of the most knowledgeable riggers here. His posts usually require more study than most, because of all of the info that is contained in them. He has a website as well, which greatly helped me learn knots, rigging, cutting, etc.
 
Murphy, I never thought I'd hear the Humboldt being promoted from the east coast! I can't imagine feeling as good about an inch or two of stump shot on a conventional in that situation.
A couple questions for you... why the vertical speedline on the last cut? And, if you were doing that same job tomorrow, would you make those same cuts?
Thanks for the update forestkeeper, reading Kenny's posts has become a real hobby of mine. I do pretty good these days, but he always loses me on the last paragraph.

I suck at cutting a humboldt from the ground, but make them work when taking out tops ... They are crucial for jumping tops and keeping a top that might hang up on other trees from coming back over the cut... Those cuts if made today would be close, probably same narrow humboldts, just pointing steeper downward...

the vertical speedline was used to keep the buts from those big tops from swinging out away from the base of the tree when the tops brushed and slowed, which almost certainly would have been enough to send the tips of the tops back at the tree/climber .... Keeping the buts close to the trunk ensured the tips would go to the lay after impact.... I didn't use a VSL on the small cut, which did end up coming back at me.. that wasn't big enough to hurt, but would have been a hassle if we didn't have a skid steer on site.. I was more concerned that other big tops could have ended up going back on the house w/o the VSL.

I made a significant mistake with that last cut, by having too much pretension on the pull line. I wanted to get around to the other side of the tree before calling for the pull, so that stub would protect me if the but had come back over the cut.. That top was big enough to get me in real trouble if it had... So I got lucky on that one... It was close as can be seen in the slow motion close up..
 
Fk, they are talking about treespyder, who is also named Kenny. He's a walking encylopedia of tree work, and has studied rigging from sailing and other trades to become one of the most knowledgeable riggers here. His posts usually require more study than most, because of all of the info that is contained in them. He has a website as well, which greatly helped me learn knots, rigging, cutting, etc.
Thanks for the clarity -- I was thinking Kenny Sanchez at first. Yes, I am a student of thetreespyder as well, studying his posts and soaking in the info over time. Always helps to be continuing to sharpen the skillset!
 
Fk, they are talking about treespyder, who is also named Kenny. He's a walking encylopedia of tree work, and has studied rigging from sailing and other trades to become one of the most knowledgeable riggers here. His posts usually require more study than most, because of all of the info that is contained in them. He has a website as well, which greatly helped me learn knots, rigging, cutting, etc.

Kyle, my friend...you are both correct and so wrong all at the same time :). Kenny treespyder does pack a lot of information into his posts...but the reason it takes serious study to pick it all out (if one can at all :D) is because Kenny does not use language like normal people do.

Hell, look at any number of posts by Jerry Beranek, or Stig, or even me...clarity of communication is a priority in our attempts at passing on the reason we do things the way we do, what the objective is and how you can get there in easily understood methodology. I only mention a few outstanding examples of the art. There are plenty more members here that can and do achieve the same every day.

My friend Kenny on the other hand, makes up words, phrases, and spellings left, right, and center. All from inside his own brain. It's a supremely gifted brain...but eff me, it can be beyond most normal people to interpret his thoughts much of the time.
 
Like i said, a lot of info :lol: i thought it best to ignore the obvious... his lack of syntax does... sometimes interfere... but he's incredibly knowledgeable. His pictures help where words sometimes fail too. :)
 
:lol: Yep.

The sad thing is, that many, many readers of his posts just skip on by because he is so hard to decipher. That is a shame.
 
i kinda think in a Humboldt, the front fibers on the anchor/stump side of hinge aren't braced back as far, can flex more easily forward.
It also gives it's own stump shod/block against slide back.
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i think the downward and across forces exerted by fall for any given length x angle x weight of CoG to pivot will give same cos/columSine vertical forces and also same sin/sideWays horizontal forces, from there the rest is mostly on how anchor/stump receives the forces and when faces close.
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The downward ramping serves an easier slide to the ground w/o usual full face punch back upwards like full face Dutch that a conventional hinge has.
This saves the high dollar end of spar by not cutting it,and sliding more than smashing to stump and rebounding to ground.
Perhaps allows less control needs, and fiber that is flexing easier also is less needed for control, so less internal fiber pull on money end would seem.
We generally say to make sure not to cross faceCuts, always good advice unless trying for 'special effects'
But in conventional would specifically not cross lower faceCut past upper;
in Humboldt it would be upper you specifically don't want to bypass lower ;because the fault is in the perpendicular cut to the grain;that then gives the close directly up the fiber column giving Dutchman
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In conventional hinge would say not so bad to bypass w/top cut past lower, in fact in tall nonLeaning pines experimented with double-wide kerf bypass lower cut; so that tree falls free so many degrees, then hits reinforcement of lower face for sudden pulse backwards for support(this is part humboldt cuts out).
So always note angle of each cut and if gives free travel,then on close if it gives mechanical stop command (up/down fibre column) or mechanical flex command across flexible axis of fiber column i think(see similar imagery in high backcut i think!) .
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in straight pines used to play with conventional slanted faceCut double kerf bypassing horizontal faceCut; to give some free travel/flex in early tip stages(like humboldt not pushing immediately back against hinge forward flex), until closes then would machine would proceed with more of a conventional push back by lower front face on hinge/bracing hinge more. Tried to pull into the stronger hinge theory, then add brace.
Bypass slant past horizontal in humboldt however not same, as top side kerf opening pulls back at rear of kerf; trick was on bottom side key bypass close or vertical/slant it pulled to forward part of kerf across kerf. So this is where i get my imagery for lower part of conventional face bracing back against hinge flex forward.
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Kinda re-wrote this shorter 3x;hope that is enough, but not tooo much; gotta leave it here and clock into desk job (grumble); as wings are clipped (can't fly/float realistically so much on end of rope anymore).
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I'm really sorry, Kenny. Again you are not even close to understandable for the bulk of your readers.

I know you know a huge amount about this subject, as I've seen flashes of understanding get through to me over these many years we have shared online discussions...but it is not knowledge available to most of us regularly.

And that is a real shame.

It's not your fault. It's just that your use of language is unique, and thus beyond most of us to follow easily. Or even with great difficulty, frankly :).
 
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