Rigging Tip Failure

INteresting options there David...

I would be inclined to use the natural spring action of the wood in multiple rigging points, option 2.. Probably set the block on the right a bit higher.. as high as the bucket would reach... You would take advantage of both the movement of the V crotch (each side towards the other) and the movement of the two trees towards each other... That's going to absorb a lot of energy...

I double crotched a dead elm chunk once that sucked the two rigging points together...

The lack of movement in option 1 would add a lot more force on the rigging sysytem (especially given the groundie locked it up)
 
When hanging a block or the Port-a-wrap I quite often use the tail to give extra support to the loaded section of the tree that sees the load. User discretion required, always.

Edit: Well that sucks, my attached jpg shows up as 'Page not found' from here.

[image]http://www.treebuzz.com/forum/download.php?Number=377081[/image]
 
Careless or clueless (like the cameraman said) they were lucky.
Since when are jeans and Tshirts PPE?
That is the type of tree removal NATGEO seems to want.
It seems that some people will do things out of a bucket that is a bit reckless. IMO, that is a climbing tree all day long.
 
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Edit: Well that sucks, my attached jpg shows up as 'Page not found' from here.

[image]http://www.treebuzz.com/forum/download.php?Number=377081[/image]

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I get that a lot Treeco, it's because Treebuzz hasn't upgraded since 1998 or whenever it was started. In most other forums you can multi post pics/embed videos without an issue.

Treebuzz is getting very antiquated and will lose the next generation of climbers coming through because they simply wont tolerate nonsense like you experienced. They'll start up their own forum and Treebuzz will slowly die out.
 
second try

377158-Standback..jpg
 

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but why do that????

You're taking so much rope out of the system.. I'd be more inclined to use a3 blocks in the trees, and a redirect at the base of the anchor tree and set the LD as far back as practical, to get MORE rope in the system...

My approach to rigging big pieces is to set it up so even if the groundie locks it up, you're gonna be OK.. And with 3 wraps and tha much distance between man and LD, its most likely gonna lock up!
 
"but why do that????"

Physics is a lot of the reason. More rope in the system doesn't help much or at all when the load is top roped.

Tying the two leaders together works to keep the included union from seperating. The lowering point looks to be above the load making most of the load swing loading Vs. shock loading. More rope in the system when there is not shock loading doesn't do a lot. Even with a pulley on each leader the closest leader may still have failed if it is not tied to the back leader to limit it's movement.

Don't overlook the significant fact that pulleys place a two to one load on the lowering point.

I don't think the included bark leader would have failed if it had been backed up and not seen 2/1 loading.
 
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"This boy's crazy, . . . crazy as they come."

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There may be no greater feeling in the history of eating sh*t, than to have your crew gathered at that moment, singing your praise in fear and uncertainty, completely on the brink. And then total catastrophe.

It is a Roman triumph in the epic sense of a sh*tshow.
 
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"but why do that????"

Physics is a lot of the reason. More rope in the system doesn't help much or at all when the load is top roped.

Tying the two leaders together works to keep the included union from seperating. The lowering point looks to be above the load making most of the load swing loading Vs. shock loading. More rope in the system when there is not shock loading doesn't do a lot. Even with a pulley on each leader the closest leader may still have failed if it is not tied to the back leader to limit it's movement.

Don't overlook the significant fact that pulleys place a two to one load on the lowering point.

I don't think the included bark leader would have failed if it had been backed up and not seen 2/1 loading.

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Tree Co, thanks for adding to the discussion. be sure not to get bothered by questions of "why do that" or "that is not right" or whatever. Appreciate those that can speak up and put it out there. AND add a diagram.

I definitely like using the tail of something to join to the other side. I helped add that to the TCIA rigging manual.

I don't have much experience with putting all the friction up in the top of the tree, so a person shouldn't knock it unless they have tried it. I can only speculate.

I do like lots of rope in the system like Daniel says. It does SEEM like a short amount of rope between the LD and the falling piece would not be good, but again, I haven't done that with big weights, only light stuff.

With the chance of sounding like an advertisement plug, that's what I love about the X-Rigging Rings, it's a share between both of your systems. The LD is at the base of a tree with lots of rope in the system, but there are little friction points along the way so it's not putting double the force on the rigging point.

I like rigging discussions.
 
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Edit: Well that sucks, my attached jpg shows up as 'Page not found' from here.

[image]http://www.treebuzz.com/forum/download.php?Number=377081[/image]

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I get that a lot Treeco, it's because Treebuzz hasn't upgraded since 1998 or whenever it was started. In most other forums you can multi post pics/embed videos without an issue.

Treebuzz is getting very antiquated and will lose the next generation of climbers coming through because they simply wont tolerate nonsense like you experienced. They'll start up their own forum and Treebuzz will slowly die out.



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I love treebuzz. But have to agree. I know a couple of young guys (students) that tried getting on here and didn't get through for some reason or they got lost. Told them to contact Tom but unsure if they ever did.

Maybe start a new thread.

Back to rigging...

edit: mean't thread not forum
 
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I don't have much experience with putting all the friction up in the top of the tree, so a person shouldn't knock it unless they have tried it. I can only speculate.

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David, I hang pieces of trees from a port-a-wrap quite frequently, even locked off on the Porty. The anchor point if often over an area where I can reach with the bucket truck then slice and dice the section up letting it free fall. It takes some of the work load off of my single ground guy as he drags the brush out of the way towards the chipper then I lower the large wood to the ground. I never 'negative block' onto a Porty though as its design is not secure if slack can develop in the line. Lots of big swings though.

Something not mention yet, or if it was I missed it, is how a top that is hinged away from the lowering point can expose the lowering point to some very high forces as the system can behave as a class 3 lever if no slack is given as the piece folds over. http://www.technologystudent.com/forcmom/lever1.htm

Class 3 lever force may have been a major cause of the included bark leader failure.
 
BTW, speaking of having trouble posting attachments: I did exactly the thing the second time around and it posted fine.
 
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Edit: Well that sucks, my attached jpg shows up as 'Page not found' from here.

[image]http://www.treebuzz.com/forum/download.php?Number=377081[/image]

[/ QUOTE ]

I get that a lot Treeco, it's because Treebuzz hasn't upgraded since 1998 or whenever it was started. In most other forums you can multi post pics/embed videos without an issue.

Treebuzz is getting very antiquated and will lose the next generation of climbers coming through because they simply wont tolerate nonsense like you experienced. They'll start up their own forum and Treebuzz will slowly die out.



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I love treebuzz. But have to agree. I know a couple of young guys (students) that tried getting on here and didn't get through for some reason or they got lost. Told them to contact Tom but unsure if they ever did.

Maybe start a new forum.

Back to rigging...

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It took awhile for me to get my log in squared away. I bought idotreework.com years ago with the idea of starting a tree forum. Maybe someday.
 
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"but why do that????"

Physics is a lot of the reason. More rope in the system doesn't help much or at all when the load is top roped.

Tying the two leaders together works to keep the included union from seperating. The lowering point looks to be above the load making most of the load swing loading Vs. shock loading. More rope in the system when there is not shock loading doesn't do a lot. Even with a pulley on each leader the closest leader may still have failed if it is not tied to the back leader to limit it's movement.

Don't overlook the significant fact that pulleys place a two to one load on the lowering point.

I don't think the included bark leader would have failed if it had been backed up and not seen 2/1 loading.

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We have a difference of opinion!.... That top was 40' tall.... and you're gonna "swing load it" and avoid shock loading... The whole reason he cut it there, was that the bucket was maxxed out... How's he gonna set a block higher than that? AND swing out a 40' top.. That's ridiculous...

And this statement.... "Even with a pulley on each leader the closest leader may still have failed if it is not tied to the back leader to limit it's movement." I disgree.. Figure the vectors ... it wasn't going anywhere..

And then you go on to talk about pulleys adding a 2:1 MA.. That is simply not applicable to this situation.....

And I don't need a diagram to see or show that the piece is going to shock load David!
 
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That top was 40' tall.... and you're gonna "swing load it" and avoid shock loading... The whole reason he cut it there, was that the bucket was maxxed out... How's he gonna set a block higher than that? AND swing out a 40' top.. That's ridiculous...

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Murph,

There is no need to get nasty. We are simply discussing what may have been better rigging options that what was showed in the video.

The video shows the boom at a pretty good angle when the cut was made and the rigging crotch pretty much beside the boom pedestal. There may be exceptions but usually reach is higher the closer to the pedestal and lower when the boom is at an angle.

To swing that top towards the rigging point I would have removed that one limb still on the trunk(it caught the rope) and cut so the fall was not directly in line with the hinge and the rigging point so the rope would not hang up on the butt.

I don't think two blocks, one on each leader is a bad idea, but I would still have tied the two leaders together so they were supported from going 'their seperate ways'.
 
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And then you go on to talk about pulleys adding a 2:1 MA.. TOTAL ignorance... unbelievable.....



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Murph,
The 2/1 ratio was a 'mechanical disadvantage' in the context in which I used it..........meaning using a single block would place 'twice' the load on the rigging point. Using no block at all also placed twice the load on the rigging point but it would be somewhat less than twice due to friction(rope burn?).
 
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