#43
Any thoughts on how to set this up remotely? I'm using a pole saw to throw a bight over a redirect, then bring that bight back to my saddle to clip into a biner. This gives the same 3:1 MA, but does involve some rope on branch friction.
 

FreeFallin

Well-Known Member
#44
Hmmm, sounds like you are remotely setting @yoyoman s on bight (or M bight) redirect remotely. That's interesting all by itself. I hadn't considered setting the 3:1 remotely and then using it to pull yourself to it, that kind of backwards thinking is exactly what I like though. Might be worth experimenting with.
 

rope-a-dope

Well-Known Member
#51
I tried scamming this huge white oak in two different spots.
The first one I skipped over the 3:1 because I planned to work a big section of tree and didn't want to eat up rope coming down to the low limbs. The set up is exactly the same until its time to pull the bight thru and clip it on your bridge. Instead I clipped the rope above and below my system so the tail is pulled to retrieve after taking off the gear.
I did my work and got back to my tail and pulled. Dragging the rope tail thru the canopy and redirect made it twist up real bad so the ground had to help pull hard to get the hockles on the bight to pop thru the biner. Then the biner got jammed in the bight. I couldn't flick it because of rope path so i needed rescue (multiple climbers were in the tree already, so assitanse was immediate).
Retrieval is working best with a direct rope path to the rediect so flicking can help shake the biner loose of the bight. 20171026_120425.jpg
This was my second scam that day, original set up. See how the twists on the top of the biner have stretched out thru the 1st bight? I think this may cause a "sticky" retrieval or the size of the rock pirate. I had to shake this one loose for a while with some vigorous whipping
 

FreeFallin

Well-Known Member
#52
Wondering how this might help out on the milticender carabiner, for the captured bight...

View attachment 47623
That's pretty cool, I can think of a couple of things - for one that is a good option for either end of the MA system, for someone on a budget that is not happy with the level of friction. A roller carabiner is around $45.

This also allows you to use a carabiner with a higher kn rating on top. The Petzl roll clip is only rated at 20kn, this is not an issue for this system since the carabiner is only responsible for 2/3 of the life support, but it would be nice to have a more robust option.

Below though... it adds a little complexity, but not nearly as much as the other pulleys I tested at the bottom.

Nice find!
 

FreeFallin

Well-Known Member
#53
I tried scamming this huge white oak in two different spots.
The first one I skipped over the 3:1 because I planned to work a big section of tree and didn't want to eat up rope coming down to the low limbs. The set up is exactly the same until its time to pull the bight thru and clip it on your bridge. Instead I clipped the rope above and below my system so the tail is pulled to retrieve after taking off the gear.
I did my work and got back to my tail and pulled. Dragging the rope tail thru the canopy and redirect made it twist up real bad so the ground had to help pull hard to get the hockles on the bight to pop thru the biner. Then the biner got jammed in the bight. I couldn't flick it because of rope path so i needed rescue (multiple climbers were in the tree already, so assitanse was immediate).
Retrieval is working best with a direct rope path to the rediect so flicking can help shake the biner loose of the bight. View attachment 47631
This was my second scam that day, original set up. See how the twists on the top of the biner have stretched out thru the 1st bight? I think this may cause a "sticky" retrieval or the size of the rock pirate. I had to shake this one loose for a while with some vigorous whipping
Wow, excellent testing and feedback, thank you!

That is a big carabiner to pull through, was it difficult because it was against the branch, or because it just wouldn't slip through the bight at all?

I have noticed the spreading knot occasionally, but it does not seem to affect the function or strength.

A larger carabiner might require a looser bight around the redirect point to give more loop to slip out of.
 

rope-a-dope

Well-Known Member
#54
The bight was pretty tight and close to the supporting branch. I realized after, the looser tied scam is easier to pop out but still secure. Kind of like a floating anchor.
I'm thinking about the quickie now, but the pin sticking out could cause wierdness. I think I have a mighty mouse I could try as well.
I just love it when the cool trick works. Totally makes up for all the climber embarrassments!
 

FreeFallin

Well-Known Member
#55
The bight was pretty tight and close to the supporting branch. I realized after, the looser tied scam is easier to pop out but still secure. Kind of like a floating anchor.
I'm thinking about the quickie now, but the pin sticking out could cause wierdness. I think I have a mighty mouse I could try as well.
I just love it when the cool trick works. Totally makes up for all the climber embarrassments!
Love it when the tech works!

You discovered the same thing I did, I did some testing to see if the SCAM could be adjusted tighter, to allow the climber to decide how much of the load remained on the tip, or to direct some of the force down the redirect branch in a more natural way, kind of a zen/ use the force idea, but I found that if it was too tight the loop got smaller and the carabiner took some shaking to pop through.

The quicky would be a little slower to setup, but should work. Do you know if it has the same kn rating all the way around? I think it does, in which case it would not matter if it spun to the side or something.
 

deevo

Well-Known Member
#56
Hey all, I have been playing around with this for the last few months and I think there is enough here to release it into the wild. I am calling it Single Carabiner Access Method (SCAM), because it needed a simple name, and the ideas are likely a conglomeration of things I ripped off ;)

As a rec climber, my intent here is to contribute to this community with what I have to offer, that being a basic knowledge of physics, a love of climbing, and the annoying habit of overthinking everything. In this case I have been working on a 3:1 MA system that is simple, remotely retrievable, self tending, can be used as a redirect, and can be setup by adding a single carabiner in the tree. I realize I am not the first person to wrap a rope around a carabiner, but the overall methodology is something I have not come across yet in my constant reading and watching of all of you.

The first video explains the basics of what I set out to do and how to setup and use a SCAM 3:1 mechanical advantage. It is a ramble, skip ahead if you don't need all the physics and logic behind what I am doing:

The second video is shorter and expands to include the SCAM Redirect and how I am using it in the tree:

Special mention to @yoyoman for kicking off my thought process, and @Tom Dunlap for the slack tending idea. Feel free to give me feedback, I am always looking for input on safety, usability, and potential ways to improve. :coffe:
I tried it today with the rope runner and was Pretty darn impressed ! I ordered the Petzl Rollclip Z get it from tree stuff last week, get it from @treebilly when we meet up at the expo this week. Will make it even better! Thanks for sharing and hope to use it as much as I can even though I don’t climb as much anymore
 

FreeFallin

Well-Known Member
#57
I tried it today with the rope runner and was Pretty darn impressed ! I ordered the Petzl Rollclip Z get it from tree stuff last week, get it from @treebilly when we meet up at the expo this week. Will make it even better! Thanks for sharing and hope to use it as much as I can even though I don’t climb as much anymore
Thanks for testing this out deevo, I pictured it working well with the runner but had no way to test, that is great to hear. (y)
 

FreeFallin

Well-Known Member
#59
Quickie's side loaded rating is 15kN if I remember correctly. 30kN loaded in the curve and pin.
So at first glance that seems rated under life support if the quickie happened to side load, which is possible with a lot of unloaded shaking.

However... the SCAM system suspends the load (in this case Rope-a-dope) on 3 legs, the carabiner (or quickie) is only supporting 2 of those legs, or 15kN of the required 22.5kn to meet the minimum life support rating (this is also how I justify using a Rollclip rated at 20kn in the video).

So at the end of the day a quickie would technically be rated for life support in this system even if it is side loaded, but seems like a little extra work for a little less safety to me.
 

SomethingWitty

Well-Known Member
#60
So at first glance that seems rated under life support if the quickie happened to side load, which is possible with a lot of unloaded shaking.

However... the SCAM system suspends the load (in this case Rope-a-dope) on 3 legs, the carabiner (or quickie) is only supporting 2 of those legs, or 15kN of the required 22.5kn to meet the minimum life support rating (this is also how I justify using a Rollclip rated at 20kn in the video).

So at the end of the day a quickie would technically be rated for life support in this system even if it is side loaded, but seems like a little extra work for a little less safety to me.
Just have to ask, have you played with a quickie?
Anything that cinches is hard to make side load because of the taper on the curved piece, and the pin both rotates and has those nice corners to hold your bight in place. I think the quickie might have found another calling. I'll try your nifty new trick out with a runner and my wrench with a HC pulley.
I think a carabinier in the middle hole of the HC may be the solution to the cluttered wrench binier. I never switched to the fancy pulleys that don't have extra holes. A pinto could use the becket, I guess.
 
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