Help with Pulley System

Jim W

Just to clear things up. I am not suggesting to use it for Search and Rescue. i would not make a statement of that nature becuase we do have methods that work well and have been around for sometime(as you have pointed out).
I think my statments have been miss read and read into too much. What I was saying is that we where around and they see nothing wrong with it. We were sharing ideas and tried them out. They climbed on the system and said positive things about it-- they like the system. But it was never been written or stated that it should recommended for Search and Rescue.



We choke it off, I will try to get a photo for you.

We did try it the way you where talking about and it can creep. We did the test simular to Treeman's, but you have to do alot of jerking and thrashing.

Concerning the extra rope for rescue. review back into the files on this thread and you will notice that two diagrams have been made with an extra rope that is used to hold the system. It is simular to how the PACK system is set up. This would allow a climber to be rescued by using a ground base lowing system. This is a good idea.

Wildrice, thanks for the clarification about using the SS for rescue work---sorry I misunderstood.

I do not know about the PACK system. Can you provide a link to its description? Thanks.

Your tagline, “Mother Earth- Our Most Sacred Heirloom,” is very good. There are a lot of people out there who don’t seem to realize that. I hope they wake up pretty soon!

Hi,

Think both of us are here for the same reasons to better Canopy-Adventure-Recerational,-Educational Technical Tree Climbing.

With that understand . Lets look at this as a team and see where it takes us.
I will strive to use txt that should be taken Lit. that way we do not miss understand the meaning.


First, the OSHA comment. He is OSHA certified. He says that the Super System is a nice system. However, it is not mentioned with in the OSHA standards/regs.

I believe it is a good point to notice that individuals from diffenent backgrounds have noted. However, we could all find people from different backgrounds that would support or not support the Super System.

With this discuession I am looking to see if the Super System could be improved(it is a creat system all ready) by using one rope.

It needs to be simple. Do not make it very difficult to set up, if it is then you increas error and that is bad.

Before we start this journey I will do my best to discribe the two rope system that is used with the PACk, but I will use it with the Super System instead.

The lowering rope is first put up over a limb. YOu attach the PAW or what ever you are going to do to rig the climbing rope(that is the second rope that is used to create/rig the Super System).

You set up the Super System and Raise the it up by pulling down on the tag end of the lowering rope.

Have at least a wrap 3 pull 2 life ranted webbing around anothe tree. Hook a rack with atleast 6 bars w/hyper bar(have a rack that has dual hyper bars). Feed the lowering rope through the rack and tie it off.

This will allow you to lower a climber with control by using the rope.

I will try and learn how to take the diagrams and post them below this posting for easy reff.

Once this is cleared up I wold like to see what we can do as a team to :
With this discuession I am looking to see if the Super System could be improved(it is a creat system all ready) by using one rope.

Ok I need help. Please give me directions how to post txts or images that some one else has posted?

We use the SS with a saver and knots. We also have the choke all away agianst the limbeand it is very snug. I wonder if it is being set up with some slack or not having the choke up agains the limb?

I wonder if one could set the choke on a diffent rope(I have always seen the choke attached to the F-8-On a Bight-- that is the same F-8-On a Bight as the pully is attached. Could you have another connection just below the saver on the down roope? Could a prussik(Give me some leway becuase I do not recall how to spell prussik correctly at this time) or some type of ascender?

To post an image that somebody has posted, right click on the image and choose 'Save As...' put it somewhere on your desktop. Then, when you are making your post, push the Browse button under the spot where you type your message, and find the file you saved.

- Link

Setup:
Usual Super System setup with running choke using Delta.

New Additions to setup:
3/8 inch “balance line” setup over the branch as suggested on the opposite the running side of the rig. Line pulled taught and tied to a small tree nearby.

Here’s what I found:
I jerked the line vigorously. There was no creep. An assistant placed a hand on the 3/8 inch balance line. A few vibrations could be felt on this line when I became the bigger jerk…………..uhhhh……jerked harder.

Wildrice is right. We need some team work here. I suggest teams of 3 to hash out alternate system ideas. Each team should take one idea and run with it. The U2U feature here might be a good way to do it. The more ropes and complications for the rig invites errors. Simplicity is golden I believe. We need to get it set up right and right every time before we send someone else aloft.

And who knows- maybe the original system with a few tweaks is all we need.

Wildrice posted on 23-5-2007 at 07:38

First, the OSHA comment. He is OSHA certified. He says that the Super System is a nice system. However, it is not mentioned with in the OSHA standards/regs.

There are very many OSHA “certifications,” including personnel management, hazardous waste management, fork lifts, etc. etc. The question is, does the “certification” he possesses indicate that he has the capability and authority to evaluate rigging systems, including proper engineering static-force analyses of pulley systems and other mechanical systems? (I am confident that the answer is “no.”) That kind of knowledge is what is required in order for his comments to be meaningful.

I am glad that he thinks that the system is “nice,” but until he comes forward and shows his credentials, I have to believe that he does not have the competence to make such judgments. Sorry.

I still am waiting for an “OSHA certified” person to show up here and discuss this system. Until that happens, all claims of the “I know a guy who knows a guy who said . . . .” variety have no known authority for their proclaimed truth and thus are of zero value.

There is a good reason the SS is not mentioned in OSHA regulations: If it were, it would be given as an example of poor engineering design---a flawed design---an example of what not to do.

Wildrice posted on 23-5-2007 at 07:38

With this discuession I am looking to see if the Super System could be improved(it is a creat system all ready) by using one rope.

Treeman posted on 24-5-2007 at 12:08 AM

Wildrice is right. We need some team work here.
....
And who knows- maybe the original system with a few tweaks is all we need.

First, (for the jillionth time) the SS is not a great system. It is a poorly designed and flawed system.

Next, I agree that tweaks probably are all that is required. At least three acceptable modifications already have been presented in this thread. I think Mark’s design, posted on 5-11-07 at 08:21, is very good in that it allows for a quick rescue from the ground. Geof described a similar system on 5-11-07 at 10:46. He then posted a diagram on 5-11-07 at 22:12. Considering that the primary reason for having this system seems to be for facilitated climbs for handicapped climbers, that seems to be a very good thing.

I think that Link described something, too, but I wasn’t able to locate it.

I think that the simplest modification to the SS is the addition of a small line that will counter the unbalanced force at the limb (see Treeman’s “Test 3”). Remember, the maximum value of that force is one-third of the weight supported by the system, so a small accessory cord could be used. See my post of 5-9-07 at 00:36 for details.

HOWEVER, before one goes off in further attempts to solve the problem, s/he should ensure that s/he understands the problem. If one cannot understand the engineering analysis that indicates the problem the Superflaw System has, then s/he cannot expect to solve the problem.

Without an understanding of the mechanics of the system, there is the strong possibility that yet another flawed system will be invented. For example, Wildrice suggested “I wonder if one could set the choke on a diffent rope . . . .”

Doing what Wildrice suggested probably would make the system more secure, but there is no guarantee because the system flaw is still present. This simply applies a fix that may or may not work, because the friction at the branch still is an unknown.

If another line is to be used, simply use it to prevent the climbing line from moving across the branch.

Jody, I truly appreciate your desire to correct the flawed system, and I don’t mean to be picking on you by my previous comments; it’s just that this example was available.

Folks, it really is necessary to *understand* the problem before trying to fix it.

Treeman, your “Test 3” is well received by me. Thanks for doing that!

That method is guaranteed not to “creep” or slip unless the rope breaks or the knot unties/slips, but that’s the same (minimal) risk we always take.

Treeman (and others) I again strongly encourage you to do the second of the two tests I earlier suggested. Here it is again:

2 --- Instead of passing the rope over a branch, run it through a pulley (in other words, use three pulleys). This will simulate what Mark and I have been talking about when we express concern about a slippery branch (e.g., as Mark mentioned, wet lichen). Warning: Approach with caution!

We know that the MA is unbalanced on one side. It remains to be seen that this causes anything beyond the pulley moving down. The pulley moving down causes zero problems for the climber. It only limits how high the climber can go (if it moves down). Isolated analysis of the MA asymmetry is not contributing to understanding the entire system.

Jim, I think it's important for you to set the original system up to understand how it behaves in practice. Without this understanding you are missing something in your analysis. I believe you will have a eureka moment when you actually use it. I'm looking forward to it
-moss

Wildrice posted on 23-5-2007 at 07:53 PM

We use the SS with a saver and knots. We also have the choke all away agianst the limbeand it is very snug. I wonder if it is being set up with some slack or not having the choke up agains the limb?

Wildrice, you may not have read this entire thread, but it is irrelevant whether the limb is choked. The problem is (a) the system is unbalanced and (b) the amount of friction at the limb is an unknown. That unknown and variable factor is the only thing that inhibits the system from collapsing.

The system has a serious flaw. Period.

Hard choking almost assuredly helps, but it does not *cure* the problem.

Please, everyone, understand the problem: The Super System has a serious design flaw. Until you understand the flaw, you can’t be expected to fix it.

moss says

It remains to be seen that this causes anything beyond the pulley moving down. The pulley moving down causes zero problems for the climber. It only limits how high the climber can go (if it moves down).
....
I believe you will have a eureka moment when you actually use it. I'm looking forward to it

Moss, if you will do the test I suggested (substituting a pulley for the branch, so as to simulate a low friction branch), I think it is you who will have the eureka moment!

I have said several times that the climber will descend---that's what I mean when I say that the system will "collapse."

I have tried it; I know.

Thanks for still hanging in there with me. We must seem like Democrats and Republicans discussing economic policy!!