question about shock loading a rope and blocking

I don't recommend those tapes.. Its been a long while since I've seen them, but it seemed like they just covered one job and showed a lot of gear on the ground. The only things that were covered were the techniques used on that particular job, which wasn't much. They could have showed so much more real practical info if they had just done a bunch of mock ups with some diagrams etc..
 
im able to get by with the rigging knowledge that was passed down to me from my previous employer. i learned how to use a porty and blocks/pulleys and where to set up a block or pulley in the tree.
i struggle with negitive rigging aka blocking/chunking. lots and lots of shock loading. as bad as that sounds that is pretty much what blocking is.
 
if you don't want to drop all that dough, you can *rent* Art & Science of Practical Rigging from Wesspur. It is definitely worth watching a couple of times - lots to learn. Buy the book that goes along with, and you can refer to that - the book is good stuff and will mostly remind you of what you watched.
 
I posted a log weight chart somewhere on here, can't get it to load again, but I keep a copy in the truck, laminated. Take a look at it or bring it up with you, may help/ Sherrill tree has a chart, but if you can find the one on here I posted it has far more species listed and info.
 
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5 posted a log weight chart somewhere on here, can't get it to load again, but I keep a copy in the truck, laminated. Take a look at it or bring it up with you, may help/ Sherrill tree has a chart, but if you can find the one on here I posted it has far more species listed and info.

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Did the same "laminated" thing. Searched and found two post with "Green Log Weight" attachments by:

Mahk Adams (link)
Norm Hall (link)

Both are spreadsheets. Norm's is smaller, so, easier to laminate. Mahk's is larger (3 pages) but more inclusive ... You can laminate all 3 pages or keep it in a plastic sheet protector so you can get to the other pages. I've never needed the third page. So, might laminate just the first two together.
 
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im able to get by with the rigging knowledge that was passed down to me from my previous employer. i learned how to use a porty and blocks/pulleys and where to set up a block or pulley in the tree.
i struggle with negitive rigging aka blocking/chunking. lots and lots of shock loading. as bad as that sounds that is pretty much what blocking is.

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How much of an expert is your previous employer as compared to the people behind ASPR?

You can get by (survive) but more knowledge can help you to thrive.


I haven't tried Dynasorb, but will buy it based on others recommendation and the concept/ testing of the product (by this I mean strength testing), and that I've taken a bunch of falls while rock climbing and using a semi-stretchy rope.


A thought when blocking down wood is that often you can crash land some of the wood into a crashpad of brush or tires/rubber horse stall mat, using the rope to slow it down and control it after impact. Often there are times where there is a dropzone, but ricocheting into things is the problem. Sometimes, I'll drop a larger top/ block by crash landing than if I were totally stopping it, but need to keep if from flipping onto a fence or landscaping.
 
Hi GUys, in reference to the original poster of this thread, and Tom D's input as with many others, please be careful, there are too many variables there to answer that question easilly. Also, as much as you want to have a strong rope...you should be careful that you dont end up making the tree the weakest link either. For more information and a demo on dynamic vs static loads check out . http://www.youtube.com/watch?v=WDIo-WZkSaM&feature=player_embedded

www.yalecordage.com/videos - its not a sales pitch, its a safety thing...
 
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[...]using the rope to slow it down and control it after impact. Often there are times where there is a dropzone, but ricocheting into things is the problem. Sometimes, I'll drop a larger top/ block by crash landing [...]

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That's pretty much what I call good roping. I don't like wood swinging around in mid air, stuff can go wrong. I want the piece to go straight to the ground in the LZ. If it has to swing to get there I don't want it to swing past, I want it to land on the first swing. It takes timing and confidence and a good pair of gloves.

Sometimes you have to stop the wood in mid-air but usually you can get it to the ground without lots of drama if you have a pro roper.
 
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You can laminate all 3 pages or keep it in a plastic sheet protector so you can get to the other pages.

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Or just download them to your phone and have it all in your pocket. A lot of people have a phone in their pocket all of the time anyway.
 
Jamie G..

THANK YOU and Yale Cordage.. That demonstration of the 21,000 lb bull line breaking on a drop test, where the 5,600 lb dynaic line holds repeatedly, is about as clear as you can get.. THE DYNAMIC property of the rope is crucial in reducing shock loads !!!!!

Did you pick that up Chip?

Leave that double braid in the truck!!!

That is part of the reason I can rig the bigger peices that you all freak out about... Only ever broke one rope... Got a little greedy!
 
Decades ago I setup a chunk for lowering, slam dunk or negative blocking are current terms. My groundie was a VERY experienced climber/rigger and understood what we now call dynamic rigging. This is in the early days of synthetic rope but still during the heritage of 'take three..uh...two-plus...wraps" for lowering. On this piece I asked for it to be locked off and then lowered. The piece went over...and the rope stretched enough to let it smash a hole in the soffit of the garage. Dang...the good thing was that my groundie/rigger was also a carpenter! The client let us do the repair and paid the full price of the job. After that, I got away from stretchy ropes.

When I rigged I wanted to know what space the load is going to take. Trying to calculate spacial rigging isn't something that I want to take on.

Double braid ropes have been my preference. Strong, durable, just enough stretch, but not so much that they are anywhere even going to bungee.

Stretch is NOT something I want much of. Too hard to calculate for. Marv taught me, in the OLD days, to take a smaller piece and know exactly what was going to happen. Good lesson to me.

Different styles of rigging...I like double-braids.
 
southsoundtree

I PM'd you, but thought I'd throw this out for anyone who's looking to buy ,Dynasorb. Not insulting anyone, but I bought some, then found this out

Dynasorb is just Polydyne. If you buy it as Dynasorb, you will pay more for say rope.

Sherrill Tree
http://www.sherrilltree.com/Professional...igging-Line-5-8

Wess Spur

http://wesspur.com/rope/yale-polydyne-58-rope.html

As you see, 200', no splice, $43 less at wes spur, and I havn't found polydyne anywhere else yet. Unfortunatley I found this out the hard way. $43 is a big difference for the exact same product.
 
I'm not sure how you interpreted that Daniel but I'm pretty sure you didn't take away what they meant you to take away. Double braid and kernmantle are the preferred construction for dynamic ropes... I've been using them for most of my life.

The point of the video is to choose the right rope for the job, that is, use stretchy rope when shock loading is expected. Polydyne IS a double braid rope and what makes it stretch and recover is the nylon inner braid. No 3-strand can touch it in terms of shock loading.

The thing to do when taking big wood is to get the block OFF the truck and use it like a professional does... that is, with double braid rope and a friction device. If you don't use professional groundies it doesn't matter though because dynamic rigging has a lot more to do with the guy on the rope than the rope itself.

You still don't have a grip on shock loading Daniel, understandable... physics isn't for everybody... and I know how much trouble it is to set a block and that you can't be bothered with it because it's 'inefficient'.

I was leaving you alone Daniel, even trying to converse with you civilly and you had to call me out... for what reason I'm not sure. The 'leave the double braid on the truck' comment is pretty far afield from the video you refer to. You leave me alone, I leave you alone, fair deal. Call me out and I'll make you look like an idiot... again. Not because I'm smart but because you basically do all the work for me.
 
Tom,
You might have taken the wrong lesson from that experience.. Are you willing to re-evaluate? With modern gear, like the GRCS, or even a little bit of sweating the rope in by hand, we can get the stretch out when needed in 98+% of the rigging scenarios we face. The stretch in the line is so important to reduce shock loads that it far outweighs any benefits of the higher tensile static line in preventing the type of damage you describe. I think if you then had the knowledge and equipment you do now, you could have easily avoided the damage while using the same rope you were using then. See if you can find something else to blame/change besides the rope.

When the rigging software came out, it became undeniably clear just how important stretch in the line is to reduce shock loads and make our work safer. This is something that world class arborists like Big Jon long understood. Having worked with him, I've seen the principle in action countless times.

And if a picture is worth a thousand words, then yale's video is about as good as a small book.. What more do you need to see.. the shock on that static line that was enough to break a 21,000 lb line. And therefore also putting that much more force on the tree. Did you watch that video? EVERY ARBORIST SHOULD..

Once again I Am amazed that an arborist with your knowledge and experience does not get that copncept. High tensile (low stretch) double braid + small pieces DO NOT EQUAL safer...

Often times it is safer to take bigger pieces, as long as you understand the forces at work, specifically how to reduce shock loads and manage vector forces. This perspective on safety can't be put neatly into little bites that fit into the ANSI standards. Its about doing the work with mazimum efficiency, to save time and energy, yet working with a level of mastery that allows for the work to be completed without an increased risk of injury, or property damage. For example taking bigger pieces when lowering to save time energy, exposure to climbing risks and struck by risks on the ground, OR notching and dropping trees that others would be calling in a crane on or roping down, in a long day of dangerous climbing, cutting and rigging.

That video says it all!!!! Dynamic rigging lines are essential to safety and productivity...

Thanks again to Yale for putting it out!!!


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Decades ago I setup a chunk for lowering, slam dunk or negative blocking are current terms. My groundie was a VERY experienced climber/rigger and understood what we now call dynamic rigging. This is in the early days of synthetic rope but still during the heritage of 'take three..uh...two-plus...wraps" for lowering. On this piece I asked for it to be locked off and then lowered. The piece went over...and the rope stretched enough to let it smash a hole in the soffit of the garage. Dang...the good thing was that my groundie/rigger was also a carpenter! The client let us do the repair and paid the full price of the job. After that, I got away from stretchy ropes.

When I rigged I wanted to know what space the load is going to take. Trying to calculate spacial rigging isn't something that I want to take on.

Double braid ropes have been my preference. Strong, durable, just enough stretch, but not so much that they are anywhere even going to bungee.

Stretch is NOT something I want much of. Too hard to calculate for. Marv taught me, in the OLD days, to take a smaller piece and know exactly what was going to happen. Good lesson to me.

Different styles of rigging...I like double-braids.

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