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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Original Post - Feb 27, 2010 - 12:53pm PT
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Just playing around with pulleys and stuff... I also figured a way to get 3:1 on the Far End Haul system.
3 to 1 Far End Haul
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Norwegian
Trad climber
Placerville, California
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Feb 27, 2010 - 01:45pm PT
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someone told me there's a girl out there,
with love in her eyes, and flowers in her hair.
thank you mark for the exhuastive research into procedural grunting.
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Klimmer
Mountain climber
San Diego
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Feb 27, 2010 - 02:34pm PT
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Yep, it is 3:1 and you will have to pull-in 3 ft of rope for every foot the pig is lifted. You will need a very long haul rope, 3 times the length if you want to haul the standard 50m-60m.
Classic Simple Machine theory within physics. You got . . .
-Levers
and
-Incline Planes
Pulleys fall under levers.
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Mungeclimber
Trad climber
sorry, just posting out loud.
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Feb 27, 2010 - 02:51pm PT
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Klimmer?
the orange is the haul line in the pic afaict. the other line is a shorter 'pull' line.
why on earth would the haul line need to be 3 times a normal length of a 60m haul line?
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Ksolem
Trad climber
Monrovia, California
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Feb 27, 2010 - 02:58pm PT
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It's the same analytical thinking he applies to the WTC conspiracy argument...
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Klimmer
Mountain climber
San Diego
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Feb 27, 2010 - 03:11pm PT
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Ok, re-look.
The first image is really all that is needed. The second image threw me off. The blue line is a "short-line" assist for the orange haul-line. So you are pumping it a short distance until the pulleys meet and then extending it again, with I would assume would be a small mass rack of gear, once the orange line takes the load.
But you still have to pull in the blue-line 3 ft for every one foot of lift.
Second image threw me off since the bottom pulley is directly shown connected to the pig. Confussing. I guess the bottom image just shows how to unweight the pig to get it initially off of anchors?
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tom woods
Gym climber
Bishop, CA
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Feb 27, 2010 - 03:32pm PT
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We used to do the two to one, with a little piggy back rig like you have set up. It worked great. You can waist haul alot. If you belay on a gri gri, the leader can be moving while you haul cuz the throw is so short.
This works in a party of three, as the leader is up and climbing, one guy hauling, the other guy cleans and unsticks the bags.
I remember that was the theory, I don't remember if it ever worked more than "sorta."
The difference is that your fixed point on the little rope is at the top pulley. I bet you could swtich between a 2:1 and 3:1 pretty fast with that system.
Try it out. When the water starts to run out, no reason for the 3:1.
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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Reply - Feb 27, 2010 - 04:03pm PT
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I counter the "you have to pull 3 feet for every 1 foot the bag moves up" with "Jeez, what an idiot I am for trying to use a technique that uses three times less effort"!
I will gladly haul that green cord 450 feet so my little, tiny, weak and old body can haul a 300 pound bag with only 100 pounds of effort. I'll get so tired merely using not all of my body weight to raise the bag! I'll feel so less tired and worn out at the end of the day, it's simply not fair!
Coz, yeah, I thought about that, you don't want to fight the bag too much when it gets stuck, you would be applying a hell of a lot of force right away to it. That's why I figured out the 3:1 Far End Hauling also.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Feb 27, 2010 - 06:25pm PT
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Wow! Look at all of that bold text!
Even for lightweights soloists like Mark, I don't think he will need to use a 3:1 Far End Haul, no matter how heavy his pig, nor how slabby his haul. 3:1 would be very cumbersome and involve a lot of cord pulling, and jugging up and down on your separately hanging lead rope, I would think, but I've never tried it. Never had to.
With a regular Far End Haul, which gives you a 2:1 mechanical advantage, you have two huge advantages being at the bag that you don't get when you are 2:1 hauling from the upper station:
1) You are able to pull up on the pig with one hand, while you are sitting down on the free end of the haul line, on the other end of the zed. This increases your mechanical advantage to 3:1.
2)The reason you have to Far End Haul in the first place, rather than haul from the top station, is because your pig hung up on something while you were solo hauling. You could convert to 3:1, but if your pig's stuck, it's stuck, and you'll just break something or more likely give your haul line a core shot - been there, done that, at least twice.
So your problem that causes you to Far End Haul is friction, and if you are simultaneously pulling up on the pig as you 2:1 "regular" Far End Haul, then you are also pulling the pig away from the wall, thus almost eliminating friction against the rock.
So I think when you combine these two factors - pulling up on the pig to increase mechanical advantage, and pulling outwards on the pig to reduce friction, I don't see any situation where even a lightweight soloist like Mark would not be able to Far End Haul his pigs.
You almost never use a 2:1 haul if you can get away with 1:1, and the same is true for 3:1 compared to 2:1.
I really like Mark's 3:1 Hauling Ratchet, although it will necessarily require 5.5mm no-stretch Spectra zed-cord in order to work. This will certainly be easier to set up than a traditional 3:1, which requires you putting all your pulleys directly onto the haul line. More significantly, you will not have to do all those annoying "resets" you have to do with a regular 3:1 setup.
I look forward to hearing how his 3:1 hauling ratchet works. I will be he won't use the 3:1 Far End Haul, but will use the 2:1 Far End Haul a LOT, especially down low where the wall angle is low.
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tolman_paul
Trad climber
Anchorage, AK
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Feb 27, 2010 - 06:30pm PT
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Just to be a nit picker (nose picker?) you don't quite get 1/3 the effort with the 3/1 ratio due to frictional losses.
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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Reply - Feb 27, 2010 - 06:51pm PT
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you don't quite get 1/3 the effort with the 3/1 ratio due to frictional losses.
And nor do you quite get 1:1 or 2:1 either. Having good pulleys is one way to get closer though.
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tolman_paul
Trad climber
Anchorage, AK
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Feb 27, 2010 - 07:01pm PT
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A good pulley beats the heck out of trying to haul over a biner.
Of course the opposite is true in other situations. When I was a noob I set up a tr using a pulley instead of doubled biners. You definately feel every pound of the climber if he falls or hangs.
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Klimmer
Mountain climber
San Diego
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Feb 27, 2010 - 07:35pm PT
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Hey Mark,
I'm not making fun of you at all. Yes, I am completely agreeing with you. I just didn't "see" the proper set-up at first.
Work = Force X distance: and this is why we use simple machines . . .
On the end you pull (the input end):
1/3 the force you have to generate to lift the pig X 3/1 the distance you have to pull.
The end that lifts the load (the ouput end):
3/1 the force you pull with to lift the pig X 1/3 the distance lifted than the rope you pull-in.
Work input = Work output. It is easier on the human body to go long distances with small forces, than to go short distances with with big forces. Yes, that is why we use simple machines. In other words we get a mechanical advantage. Once again, I'm agreeing with you.
All simple machines are very efficient. You can tell just how efficient your pulley system is if you do the following calculation:
Your theoretical Mechanical Advantage = 3X
Your actual Mechanical Advantage = ?
To calculate actual MA:
Output Force (Weight of the pig in pounds)/ Input Force (what you actually have to pull with in pounds to lift it) = Actual MA
To calculate efficiency:
Actual MA/ Theoretical MA X 100 = % efficiency
I would guess it will be high approx. 80% or higher depending on the quality of the pulleys used.
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Bulldog
Trad climber
Yosemite, CA
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Feb 27, 2010 - 08:15pm PT
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Yo Mark, do a double haul, get another hauler, another haul line or dynamic line and haul your 100-150 lbs., each. I prefer to space haul. What route are you drooling over.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Feb 27, 2010 - 08:25pm PT
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Kevin - did you do two hauls on Albatross? How's Gretchen and Missy?
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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Reply - Feb 27, 2010 - 08:50pm PT
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I'm planning on soloing Grape Race to Tribal Rite this June. I'm planning on taking 10 days on the route but having two gallons of water extra so 12 gallons all told. 12 gallons of water weighs almost exactly 100 pounds. I've estimated the other part of the load to be about 150 pounds so 250 pounds when I leave the ground. I'll be hauling up the first three of the Nose and then quite a few on the Salathe Slab. The slab does get steeper and steeper and the bags will get lighter and lighter but I'm just hedging my bets by making sure I have a technique to haul that much weigh up the slabs. I've thought of two hauls but that would also mean two haul ropes, which I'm sure, once i reach mid height, I won't need. Once I get to Tribal Rite, three or four days into the adventure, the bag will be 30 or 40 pounds lighter and the rock will be that much steeper and I'm sure a 2:1 set-up will work fine.
I wasn't meaning my post to you Klimmer, it's just that the "pull 3, get 1" is the standard argument against it when I tell someone about 2:1 or 3:1 hauling.
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Norwegian
Trad climber
Placerville, California
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Feb 27, 2010 - 10:51pm PT
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klimmer you'd need 3x the rope if the line was fixed at the pig, then traveled up to the anchor thru a pulley then back down to the pig thru another pulley and then back up to the anchor, thru one last pulley. you pull the rope on the windward side of the third pulley.
you'd pull up three questions and only get one answer.
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SteveW
Trad climber
The state of confusion
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Feb 28, 2010 - 12:22am PT
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Mark
WE WANT PICTURES!!!!!!!
please
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Lambone
Ice climber
Ashland, Or
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Feb 28, 2010 - 01:21am PT
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I've done some 3:1s with big pigs before. Personally I'd rather grunt a lil harder and spend 1/3rd the time hauling and more time chillin.
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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Reply - Feb 28, 2010 - 12:26pm PT
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Space, yeah, well, ain't that a bit hard? I'm not that good at aid climbing. Maybe after I get my feet under me, so to speak. I've done the right side of the Tower, twice actually. Once on an attempt on the WOEML and again when I finally did it.
That crack on Grape Race certainly looks free climbable, doesn't it?
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David Wilson
climber
CA
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Feb 28, 2010 - 12:36pm PT
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mark, i'd strongly recommend the two haul lines and the split haul in favor of the ratchet. i tried the 2/1 ratchet ( granted, for the first time ) and even with that it felt like a ridiculous number of body movements for very little pig movement. i wished i'd just trailed another line and split the loads. also, just in terms of horsing things around at the belay, i found it disconcerting to have so much weight on one rope / system.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Feb 28, 2010 - 12:45pm PT
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David - have you soloed El Cap using two haul lines? I've never seen anyone do that. I want to know if that's what Kevin did on Albatross. When climbing with a partner, two smaller hauls is definitely faster and easier than one bigger/heavier haul. I'm thinking in Mark's case, though, because he is on low angle initially and will probably have to do lots of Far End Hauling, that splitting the load into two would be more trouble than it would be worth.
Coz, I think Mark's going a good way. Not only has he done the other route before, so Grape Race is new for him, Grape Race is seldom climbed, and his might even be the first solo ascent of it. I'm not sure if Mark would climb it in its entirety, as I'm not sure where it officially ends.
The climbing up to Lay Lady and above is more ponderous and painful than it appears. Grape Race has more free climbing, especially at the bottom and top, and I think Mark could get up it faster. Plus, it's just so much cooler.
I'd love to climb Grape Race, I just have to find a way to finish on something I haven't done. Can anyone here free climb? Let's do Grape Race to Genesis. I should ask Shipoopi about Genesis, and the bugger owes us a trip report, too.
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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Reply - Feb 28, 2010 - 12:47pm PT
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I have the 2:1 totally figured out and it really sings for me, but I know what you're saying.
Did I mention that I recently went over to the local sports club wall ( I know the owners) and hauled a 300 pound load, quite easily, using a 2:1 system? Granted the wall was vertical and there was virtually no drag but it wasn't that hard, to tell you the truth.
Nanook soloed Grape Race and did a TR of it. That's what gave me the idea.
Lambone, I am totally against grunting harder when there is an easier way that merely takes more time. Don't forget, I'm an old guy, I don't heal as fast and hell, I weigh only 125 pounds!
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Ihateplastic
Trad climber
It ain't El Cap, Oregon
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Feb 28, 2010 - 01:45pm PT
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Why are you planning on taking 300 pounds of free weights up the Captain?
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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Reply - Feb 28, 2010 - 02:01pm PT
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beacuse I AM MARK HUDON AND I AM BADASS!!!!!!!
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David Wilson
climber
CA
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Feb 28, 2010 - 02:46pm PT
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pete - no idea on what's best for soloing, my comments are just for hauling in general. also, the day i tried that 2/1 was frikin hot and it was like i slowly pumped myself dry, sweating it out with that slow 2/1 system. maybe i have an unfair opinion.
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rick d
climber
ol pueblo, az
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Feb 28, 2010 - 02:57pm PT
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I just have to post this again because it is so damn funny and so damn true.
"beacuse I AM MARK HUDON AND I AM BADASS!!!!!!!"
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John Mac
Trad climber
Littleton, CO
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in reply to Pete's question:
In Andy Kirkpatrick's book Psychovertical there is a section where he starts up Reticent intending to haul wth one load but finds it just too damn hard so goes with two haul lines and two hauls.
Rather than dragging up two haul lines, maybe use a zipline to haul up the haul lines, pulleys, extra biners, etc.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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HE IS MARK HUGE-DONG AND HE IS BADASS!!!!!!1111111111111
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JBennett
Trad climber
Vancouver
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Feb 28, 2011 - 09:56pm PT
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Curious. Is this not actually an inverted 4:1? It certainly looks like the standard 4:1 configuration (fixed at the "top", moving point at the bottom, and repeated). Perhaps someone could confirm?
Thanks,
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Captain...or Skully
climber
The Seas of Stone.
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Feb 28, 2011 - 10:04pm PT
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Mike. Weren't you doggin' on my cargo hook? Just wonderin', BroMan.
;-)
I take mine.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Feb 28, 2011 - 11:39pm PT
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Mark's top photo is a 3:1 Hauling Ratchet, and the bottom photo is a 3:1 Far End Hauler.
Mark, I am curious if you have ever tried the 3:1 Hauling Ratchet? I wonder how it would work? There are times when I have had to work the 2:1 pretty hard.
I really can't ever imagine needing a 3:1 Far End Hauler, for the reasons mentioned above, because you can pull right up on the pig from next to the pig while your are 2:1 Far End Hauling to make it 3:1.
Oh yeah, and in case Russ Walling is reading this:
An adjustable daisy gives you a 2:1 mechanical lifting advantage less the friction in the buckle.
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Mark Hudon
Trad climber
Hood River, OR
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Topic Author's Reply - Feb 28, 2011 - 11:55pm PT
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Bennett, the second pulley on top changes only the direction of pull and does not add to the mechanical advantage.
Pete, Yes, Lower down on Grape Race I hauled a few times with a 3:1 set up. I used a SMC Double Micro Pulley as my top pulley. It was perfect for me right then and right there. I had a ton of stuff, the rock is pretty low angle and I weigh only 125 pounds. It did take forever though.
I was just playing around with pulleys and figured out the 3:1 Far End Hauler. I can't ever imagine need it but it's always nice to have in you bag of tricks in case something really weird happens.
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Morgan
Trad climber
East Coast
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@Pete,
I don't understand how using an adjustable daisy can be 2:1. Doesn't one end have to be fixed to get a 2:1 advantage, like you see in an assisted-hoist rescue situation. How is it different from batmanning (sp?) up a toprope apart from the fact that you can let go? It seems like the way of cleaning with an ascender and a grigri you might get a 2:1 minus the friction of the grigri and a re-direct because the ascender is a fixed point when you are pulling up.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Morgan,
Using an adjustable daisy is exactly like batmanning up a toprope.
Imagine being in the gym [if you can, it's been so long for me I can barely remember, shees] and you have fallen off the wall. You are hanging in space on a toprope while your partner holds you. Even if the toprope ran through a pulley on top, instead of a carabiner, there is pretty much no way that your partner can pull down on the rope, and pull you up.
Neither can you grab the tensioned rope upon which you are hanging, above your head, grab it with fingers of steel, and batman up the rope yourself. You just can't do it.
Yet amazingly, miraculously, if you grab the rope that runs from your belayer and his Grigri up to the toprope carabiner, and pull down on it, you can pull yourself up with just your fingers, and rather easily at that. Why? Because with every pound you pull down on the rope, you are unweighting yourself by that same pounds. Assuming there is no friction up top, if you pull down with fifty pounds on the toprope, you are pulling yourself up with that same fifty pounds. The net effect is a hundred pounds of lift - fifty by your own arms, and another fifty by the rope pulling up on you. This is a 2:1 mechanical advantage.
Put your feet against the wall for a bit of extra pull, and that hundred pounds of net force will allow you to pull yourself up the wall while your partner takes in slack through his Grigri.
You know how this works - you've felt it when hanging on a toprope. You know your partner can't pull you up by pulling down, even if there were a pulley, and you also know you can't pull yourself up by batmanning the tensioned rope down to you. But you know you can pull yourself up by pulling down on the other side of the rope.
This is exactly the same situation as you have with an adjustable daisy. If you pull the adjustable daisy with twenty-five pounds of force, you also get pulled up with the same twenty-five pounds. The net effect is 50 pounds of upward force. That's why it's so darn easy to climb your aiders with an adjustable daisy.
If you want it to be really slick, instead of using an adjustable daisy, use a hunk of skinny mountaineering rope and a mini-Trax. Then you'll REALLY get your 2:1 advantage working.
Kate has an awesome setup with three adjustable daisies made from three different coloured hunks of skinny mountaineering rope, each going to its own titanium Ushba ascender thingy. The Ushba has a cam-lock lever and not nasty teeth like a Mini-Trax or the teeth on an adjustable daisy buckle, and if she blows it and takes a hard daisy chain fall, there is an excellent chance of her system catching her, which wouldn't work in the other situation. However you should obviously do every move in the correct order so you never set yourself up for a Factor 2 daisy chain fall.
Also, if you are cleaning a steep pitch, and are using a Grigri as an ascender, you can take the free end of the rope and put it through a pulley on your jug to form a "zed" in the line. The best thing to use in this situation is a little DMM Revolver carabiner, which has the built in roller on the bottom of the crab. This pulley is super compact and is all you need for this system of cleaning. You don't want to use a crab + pulley combo because of two problems - it's an extra step to open the pulley, and it makes the upper part of the zed hang too low.
When you pull down on the free end of the rope, through the DMM Revolver, again you get a 2:1 mechanical advantage less the friction through the Grigri and the friction across the DMM Revolver. Try it and you will see. I use this ratchet when I am cleaning a steep pitch and my feet are dangling in space. If my feet are against the rock, I don't bother with the zed. I have had a partner clean all of El Cap using this zed system, some people really like it.
Cheers,
"Dr. Piton"
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Morgan
Trad climber
East Coast
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Thanks for the super-thorough response, Pete. It sounds like you and I agree that cleaning ultra-steep terrain with a grigri and one jug + dmm revolver is basically a 2:1 situation.
I'm still struggling with adjustable daisy being 2:1. I think of them more like half and half. For example, if you look at a Petzl rescue pulley with a breaking strength of 32 KN, they mean you can have 16 KN on either side of the pulley, 32 KN and Zero, or any sort of weight distribution in between.
I have used Yates adjustables and Kong adjustable fifi. Normally, I'm standing up or scissoring with my legs while pulling on the aider carabiner or grab loop. It seems like I could have a 15-20 pound weight clipped into the aluminum ring on the Yates, and it would just pull through by itself, I wouldn't have to pull on it at all.
Maybe I'm just being stubborn or ignorant, but for me, it's hard to imagine having a 2:1 mechanical advantage without one end or the other being fixed, opposite the side where the force is being applied.
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mucci
Trad climber
The pitch of Bagalaar above you
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Using a pulley and jumar hauling system, or a block roll, or a pro trax is 1:1.
but a Yates Adj daisy, (think of the buckle as a pulley) is 2:1?
Hard for me to see that. Pete can you explain the difference?
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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You guys gotta go back and read my analogy about hanging on the toprope in the climbing gym. You know you can pull yourself up by pulling down on one rope quite easily, but if you pull down on the other rope you can't even move. Why? One way offers mechanical advantage, the other doesn't.
Yes, hauling a pig with a Kong Block-Roll is 1:1, if you are pulling down on the unweighted end of the rope.
Now, go to that same Block-Roll hauling system, but instead of you being up at the station, you are down actually sitting on the pig, attached to the pig by a quick-draw so you and the pig are one. If the pig is empty, you can probably easily haul yourself plus the pig by pulling down on the free end of the rope. If the pig has more stuff in it, you will still be able to haul yourself plus the pig by pulling down on the free end of the rope coming out the opposite side of the Block-Roll.
In the adjustable daisy 2:1 setup, the buckle is analogous to the Block-Roll. Obviously the adjustable daisy buckle has a lot more friction than a Block-Roll [which by comparison is virtually frictionless] but it is still a 2:1 mechanical advantage.
Why?
In the 1:1 hauling using a Block Roll, one end is attached to the pig, and one end is attached to you. You pull down with a hundred pounds, and the rope on the other side plus the pig is pulled up with a hundred pounds.
Now imagine the pig having little arms and legs, and he is capable of hauling himself. [Don't we wish!] So now in this situation, the pig itself pulls down on the free end of haul line, not you. If the piggy pulls down with fifty pounds, at the same time he is also pulled upwards with the same fifty pounds, giving him a net upward pull of a hundred pounds, a 2:1 mechanical advantage. This is analogous to the adjustable daisy.
What's the difference?
In 1:1 hauling, one end of the rope is attached to the load, the other end of the rope gets pulled down on.
In the 2:1 situation [piggy with arms, guy dangling on a toprope in a gym, adjustable daisy] the free end of the "rope" [or adjustable daisy] isn't hanging in space, it is actually attached to the load itself. The load itself is pulling down on the free end. For every pound the load pulls down on the free end, it is also pulling itself up with the same pound.
Certainly it is less intuitive using an adjustable daisy with a friction-y buckle than say a piece of cord and a mini-Trax or one of Kate's Ushba beauties, but it is indeed a 2:1 mechanical advantage.
Maybe there's a physicist out there who can explain it better?
And here's another question for you, one which I have posed before, and could not figure out except by trying it out. Once I figured HOW to make it work best, I then was able to explain WHY. But it is somewhat counter-intuitive as well.
You have a 2:1 hauling ratchet with your zed-cord, and your zed-cord runs through two pulleys. You have a "good" pulley that is big and has nice bearings, and you have a "bad" pulley which is nowhere near as frictionless. To make it work best, do you put the good pulley on top, and the bad pulley on the bottom, or vice versa? And why?
HINT: Try this at home, using one real pulley as your "good" pulley and just a carabiner as your "bad" pulley. It will very quickly - with about one pull - become apparent where you want each pulley!
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mucci
Trad climber
The pitch of Bagalaar above you
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Now that made cents....
Thanks Pete!
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hoipolloi
climber
A friends backyard with the neighbors wifi
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I suspect good pully on bottom...
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Mighty Hiker
climber
Vancouver, B.C.
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Perhaps a pushmi-pullyu ought to be employed. One of Dr. Seuss', that is.
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Morgan
Trad climber
East Coast
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Wouldn't distance prove the point? With an adjustable daisy you raise yourself 1 foot for every 1 foot you pull down on the other side (1:1). With the 2:1 hauling ratchet, grigri/ascender/redirect ascending method, far-end hauling, you are moving the load 1 foot of distance for every 2 feet you pull down.
This is more about effort than distance: Say you had a 200 lb. crate on a concrete floor and you wanted to move it. (Kind of like hauling to Mammoth, but smoother and less steep). I guarantee it would be easier to move that crate hauling from an eye bolt fixed to the wall, going through a pulley on the crate, and the free end of the rope going to you, than it would be to have the rope tied to your waist, going through a pulley on the crate and the free end coming back to you.
In answer to your other question (edited), best pulley closest to the person hauling. Theoretical Mechanical Advantage (TMA) of 2.76T vs. 2.67T for the other way around.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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See? SEE?!
What can I say? Some people get it, and some people don't.
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Alex Baker
climber
Portland
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Adjustable daisy definitely gives 2:1. If there is 10 lbf tension on the daisy, there is 20 lbf tension on you, because it's fixed at 2 points, to you. Of course Pete already said that, in a lot of words. Yeah there's frictional "losses" and stuff that do matter, but you get the point I hope.
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Moof
Big Wall climber
Orygun
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Fish made a decent measure on one of his daisies a couple years back and concluded there are 60-70% friction loss for a net 1.3-1.4:1 mechanical advantage using Ankra buckles for daisies. Not worthless, but well shy of 2:1. In other words for a 200 lb climber to pull themselves up using only the daisy would require ~140 lbs of pulling on the strap.
Edit: Here is the link to the Fish test:
http://www.supertopo.com/climbing/thread.php?topic_id=92228
Conclusion was a 1.3:1 mechanical advantage using adjustable daisies, so 153 lbs of pull to move a 200 lb climber up. The real advantage is more around capturing progress and being able to use two hands (i.e. not needing a free hand to fifi into the daisy).
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Ah, I had forgotten about that excellent post. Read what Karl Baba and John Middendorf have to say, and especially Klaus.
I guess if you want a near 2:1 adjustable daisy, use Kate's setup with the Ushbas or a piece of cord and a Mini-Trax.
Adjustable daisies really help me a lot. Their co-efficient of dynamic friction is less than their co-efficient of static friction, which means once you get 'em moving they are easier to keep moving.
However, adjustable daisies are indeed a 2:1 mechanical advantage less the friction in the buckle.
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Morgan
Trad climber
East Coast
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Thanks for posting the other thread Moof. Most interesting. In the third to last post. It sounds like Russ and Pete aren't that far off from each other, just defining things differently in theoretical and practical terms. In the real world, I guess it's somewhere between a 1:1 and 2:1.
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Squeezo
Trad climber
Conifer CO
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mark,
good luck on your adventure this june, , Im thinking on doing my first solo on, tangerine trip in september and know my pig will be heavy and was thinking on useing a 2;1, but have no really experance on anytinbg thing like that, Can you give me a quick run down of what i need and need to do to set it up? pictures? also im headed up the nose with a bussy and she is 130 lbs and think hauling wil be hard for her, so was thinking on setting up a 2;1 for her do you think thats nessary? any help would be great thanks
squeezo
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Melissa
Gym climber
berkeley, ca
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Squeezo...if you're in a position to set up the pullies, you're ideally situated to haul the bags. ;-)
I hate having two people on the same end of the haul line (although when the bag is going to stick a lot it's still the most efficient way.) It's hard to sync, and when I'm the bottom hauler, I feel like a rat on a wheel. It's so demoralizing to jug away and just keep sinking down.
My favorite alternative, which works best when the bags aren't going to stick and there is room at the anchor for both partners to be side-by-side is to have one person haul 1:1 in the usual fashion and have the other haul 1:1 on the loaded line (i.e. Run a piece of spectra cord from their harness through a high pulley back to an inverted ascender on the loaded line. Use a munter mule to dial in the distance to the jug.)
It's so easy to haul in sync when you're side by side (especially important if both partners' peak impulse is needed to get the bag to move), and having someone haul w/ their full body weigh on the bag-side of the line seems to help break the bag's friction better too. It can also a quick and easy way to help your partner finish a haul when you arrive at the anchor after cleaning a pitch.
We started doing this when I dropped the 3rd pulley on "blast day" (doh!) making 2:1 and 3:1 single-hauler systems impossible for the entire route. Tip for idiots like me...If you're using a pulley system that involves accessory cord, don't let the pulley whiz off the end of the cord. :-(
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