Author Topic: Zeppelin- (Rosendahl-) Bend vs. Double (Trippel) Fishermans vs. Alpine Butterfly  (Read 2393 times)

Coding

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Hello IGKT,

I finally decided to have my outcome as knotting geek and registered an account in this forum  ;)
Mainly I use knots for climbing or to attach a bottle to an already full bag :D
But mainly my life is depending on those knots.

Everytime I read about a prusik knot, the loop is done using a double or trippel Fishermans knot. That is very hard to untie after it has been loaded. As of paci.com.au (page 31) the Zeppelin/Rosendahl has more advantages.
The only disadvantages of the Zeppelin/Rosendahl I could imagine in a "prusik"-loop is that you need to pay attantion in not pulling on the knot to undo it when not loaded and I think the Fishermans is easier to check after tighten it.
This is just my own opinion. But are there other people out there who might think of a Zeppelin in a prusikloop or why is it nowhere mentioned as possibillity?
I could also imagine to use an alpine butterfly bend for a prusik loop...

@Moderator:
I hope, I hit the right section...
« Last Edit: July 27, 2017, 03:30:13 PM by Coding »

JohnC

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Hi Coding

Congratulations on coming out of the knotting closet and welcome to the forum.

I can't answer your question, as I'm not a climber (well, not a mountain climber, perhaps a social climber ...)

However I often see people climbing all over this forum so someone will rappel down to your ledge and help you out.
John

roo

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But are there other people out there who might think of a Zeppelin in a prusikloop or why is it nowhere mentioned as possibillity?
I could also imagine to use an alpine butterfly bend for a prusik loop...

As long as you are proficient in executing a Zeppelin Bend, I see no problem using it.  Since there are many types of line in use, be sure to do some slack shake tests in your line, especially if it is stiff or slippery.

The Butterfly Bend occasionally has reports of possible execution error problems:  http://notableknotindex.webs.com/butterflybend.html

Then again, it is certainly possible to get an evil impostor double or triple fisherman by just forgetting to tie the other half of the knot.
« Last Edit: July 27, 2017, 11:10:34 PM by roo »
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Coding

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Thanks JohnC ;)

roo, I may make a test with the Zeppelin
And I will distrust the alpine butterfly bend from now. I would not have seen the difference when checking it. Thanks for the warning!

And thanks for your other 117213312 posts roo. You already helped me more often xD

Dan_Lehman

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I could also imagine to use an alpine butterfly bend for a prusik loop...
Because it has a famous name and so MUST be good, huh?

--whereas symmetric like knots #1452, 1425, 1408 are
symmetric and in some other ways better.  But they don't
have the sort of cachet of "butterfly".
 :(

Now, to your main question, why are you untying your
Prusik loops, anyway?  The grapevine bend shouldn't be all
so difficult to untie for whatever normal untying frequency
prusik loops have; ant it is more surely secure, as well as
more resistant to knocks & abrasion.  (SOME sources even
recommend that the very knot be put as the cross-part of
the Prusick hitch so to help keep that hitch *open*!)

--dl*
====

agent_smith

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Context is key to understanding and answering your question.

In this instance, your question is framed around a 'prusik loop' (a circle constructed from accessory cord that is closed with an end-to-end joining knot which is then used as a slide-and-grip hitch).

#1415 (Double fishermans / Grapevine) is has been the gold standard end-to-end joining knot to form the loop. However, after a period of time in real world use, #1415 jams solid.
Now, depending on your point of view, this could be a good thing.
In general, most users of 'prusik loops' intend them to be permanent.
That is, there is an underlying intention to create a permanent loop that is always ready/available for use when needed (eg in a rescue situation). Therefore, if permanence is your intention, I personally would recommend #1415 as the joining knot of choice.
However, if permanence is not an intended outcome, then #1415 would be a poor choice.

I find that I achieve roughly 5 years of service life from a 'prusik loop' - after which time, wear and tear takes it toll.
I generally use prusik loops constructed from a range of accessory cord diameters (6.0mm - 8.0mm diameter cord).

If there was an intention to be able to easily untie the end-to-end joining knot that closes the loop, then I would recommend the Zeppelin (no #ABoK number exists).

The Zeppelin can be set and dressed (in accessory cord) and then pre-loaded to further reduce the structure into a compact form. As usual, I always recommend that all end-to-end joining knots used in life critical applications have tails set at identical lengths. This serves as a useful 'tell-tale' to alert the user of any change - which can then be checked.

You will find the Zeppelin has not yet penetrated into the mainstream psyche of most climbers...it is still viewed as a novelty creation and indeed, some still feel more comfortable with what they were originally taught to use (mostly #1415).

Mark




KC

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i think an Alpine Butterfly under such loading should have consistent tension both ends
>>and loop/eye pull at right angle to mains.
>>not sure of geometry setting this at, but it can work to pull apart Alpine or @ incorrect angle the way i'm imagining usage.
.
Fisherman, Grapevine, Zep etc. do conduct force on the correct axis into lacing for strength and nip.
.
i set and seize prussiks; don't break down (as dLehman ); so never went w/Zep.
.
If quick-release prussic for lite, non-life load, not overhead i prefer a type of slipped surgeon.
.


Rope-n-Saw Life
"Nature, to be commanded, must be obeyed" -Sir Francis Bacon
We now return you to the safety of normal thinking peoples.
~ Please excuse the interruption; thanx -the mgmt.~

KC

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i guess, i change my answer some;
to hardline back to basics; lifeline prussic should be permanent / welded context as handed down to us.
The amount of jostling, closeness to working body and other hazards of usage, especially in emergency or production workplace; lend more towards the welded concept that easy to untie
.
i'd leave the Zep out of this; tho a wonderful lacing.
Add eye to eye (scaffolds) prussic .
.
Lifeline prussic should only be used for lifeline, pretty much by same person that has a sense of it's history.
After some length or questionable usage/stress; item should be downgraded to cargo dragging/not even overhead lifting or DESTROYED.
Treat this small essential link in lifeline setup like something holy and respected.
.
Part of the reasons are size:
A>what else are you trying to save that small slip of line for(?)
B>Angles of pull would be more accentuated by the least amount of offset positioning compared to a 10ft. line etc.
.
Specifically adding to Alpine Butterfly as Bend, i think Bitter Ends should be crossed a'la WhatKnot;
with all the jostling, handling, angling etc. this crossing would be harder to maintain.
Then from those considerations; perhaps easier to view don't want ANY questions on lacing,
want locked down/siezed , WELDED type strategy;
at lease i do!
.
i prefer prussic less diameter than host line, but at least 50% diameter;
flexible to seat completely and less strength loss,
on 1/2" Arborist lines i favored 3/8" coreless Tenex round that goes FLAT!
>>seats very well to grab wider, doesn't resist the bending as much as stiffer cords so maintains more usable tensile%.
>>Scaffold eyes with ends frayed or butane backspliced to button that forms stopper or tape seized down ends for good measure.
.
This is for aggressive workplace at height, day to day, twisting every which way, rolling upside down and cutting;
even been known to roll upside down, operate friction hitch with feet to descend to precarious target (or sneak down and grab buddy's hat..).
But i'd think would want to maintain concepts in other disciplines.


Rope-n-Saw Life
"Nature, to be commanded, must be obeyed" -Sir Francis Bacon
We now return you to the safety of normal thinking peoples.
~ Please excuse the interruption; thanx -the mgmt.~

Coding

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Hello again!

I tested the zeppelin "prusik" loop for a few weeks now.
I carried it with me clipped in to a karabiner, which I use to carry my keys with me.

The zeppelin is very easy to open but it seems to be TOO EASY to open.
After several days carrying it, it opened itself due to some random friction on my hip.

So I just consider it as a backup but NOT as a number one safety bend.

The alpine butterfly bend was indeed an option due to its famousness...

In the end I stayed with the double fishermans but I still dont like the fact that it becomes untieable after some time.
As endknot in climbing I prefer a bowline on a bight over a double figure 8 because it is so much easier to untie.

Brocky

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You're really limiting your choice of friction hitches by using a loop instead of a cord with adjustable eyes at each end, like the scaffold.  Plus they would be easy to untie.  It seems rock climbers and cavers only need the hitch to hold while ascending.  When doing tree work the hitch has to be able to go both ways.

Dan_Lehman

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Hello again!

I tested the zeppelin "prusik" loop for a few weeks now.
I carried it with me clipped in to a karabiner, which I use to carry my keys with me.

The zeppelin is very easy to open but it seems to be TOO EASY to open.
After several days carrying it, it opened itself due to some random friction on my hip.
Which doesn't surprise me at all; yet, do note
that I have some (hollow, nylon) binding cord
tying my keys etc. together which has been joined
by a zeppelin knot for decades(!!) without
untying (accidentally or otherwise, I think) !  It's
tails are very short & *mushroomed* so that they
in some way effect a sort of stopper against pulling
through, and otherwise are not vulnerable to being
pushed towards loosening.  So, I do respect this
knot's potential to resist untying by chance, but
it is just too *open*/loose for me to trust it in
who-knows-what-"s. happens" out-of-awareness
circumstances.
Btw, I occasionally tie various knots in my keys-etc.
clump, in small (3/16" ?) solid braid nylon (soft &
flexible, smooth), and have been dismayed to see
such things as the grapevine bend/dbl.fish
become loose, even though set firmly.
YMMV !!

Quote
In the end I stayed with the double fishermans but I still dont like the fact that it becomes untieable after some time.
But, again, consider placing the knot as the
crossing part of the hitch; that will reduce the
force upon the knot.

Another knot you might consider is what I'll
describe as a reverse sheet bend --that's
the start, only; more wraps are needed.
Begin as above described, but then take the tail
around the SParts-only of both ends at least once,
and better twice/thrice.  (One can finally tuck out
the tail of the hitching end (end doing the wrapping,
i.e.) through its initial turn.

(With one end forming a "U", bring the "hitching end"
across this U so that it turns around the U's tail,
and then around and down through the U's bight tip
hole, and around the two SParts again (& again).
.:.  One gets the sort of wrapping-tight security of
the blood/grapevine knots from the "hitching" end's
turns, but then there's a loosening mechanism that
should be amply effective at the forces expected ::
pull the U-part's tails apart, to pry out a bit of the
hitching end's SPart --enough for you to then work
loose more material, this U-part's tail, and then
the wraps.
I use this often, for its ready slack-security via the
tight wraps, and the pry-loosen aspect (and it's
a natural for diff.-sized ropes, within reason --the
hitching end being in the thinner rope).
)

--dl*
====

roo

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The zeppelin is very easy to open but it seems to be TOO EASY to open.
After several days carrying it, it opened itself due to some random friction on my hip.

You might try a Double Zeppelin Bend:

http://notableknotindex.webs.com/Zeppelin.html

(last diagram)
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Coding

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You're really limiting your choice of friction hitches by using a loop instead of a cord with adjustable eyes at each end, like the scaffold.  Plus they would be easy to untie.  It seems rock climbers and cavers only need the hitch to hold while ascending.  When doing tree work the hitch has to be able to go both ways.
I use it as a backup for my breakinghand when descending. The prusik is tied after the belaydevice and cliped into the legloop of my harness.

@Dan Lehman I am soory but can you please make some photos of the knot tied loosely. I have no idea, how to tie it.
@Roo I will try it the next weeks  :)
And the zeppelin with stoppers will also be testet

agent_smith

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Quote
You're really limiting your choice of friction hitches by using a loop instead of a cord with adjustable eyes at each end, like the scaffold.  Plus they would be easy to untie.  It seems rock climbers and cavers only need the hitch to hold while ascending.  When doing tree work the hitch has to be able to go both ways.

This doesn't make sense.
When you say 'Scaffold' - I presume you are referring to #1120 (Scaffold noose)?
If yes, this is actually a termination knot - a noose will cinch up tight - it does not have a fixed 'eye', like #1010 (common Bowline) or #1047 (Figure 8 eye knot).
There is also #409 (poachers noose) - same general structure as #1120 but with one less turn.

In general, tree climbers/tree surgeons/arborists historically use slide-and-grip hitches that are tied from a length of cord (with both ends free).
In contrast, climbers/abseilers/mountaineers historically use slide-and-grip hitches that are tied from a 'loop/circle' of cord.

There are reasons why climbers prefer to use a loop/circle of cord instead of a single length of cord.

It is also incorrect to state that climbers only need slide-and-grip hitches to work while ascending. The reverse is also very important (ie descending), particularly so in rescue situations.

Mark G
« Last Edit: September 28, 2017, 02:40:13 AM by agent_smith »

agent_smith

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Quote
Hello IGKT,

I finally decided to have my outcome as knotting geek and registered an account in this forum  ;)
Mainly I use knots for climbing or to attach a bottle to an already full bag :D
But mainly my life is depending on those knots.

Everytime I read about a prusik knot, the loop is done using a double or trippel Fishermans knot. That is very hard to untie after it has been loaded. As of paci.com.au (page 31) the Zeppelin/Rosendahl has more advantages.
The only disadvantages of the Zeppelin/Rosendahl I could imagine in a "prusik"-loop is that you need to pay attantion in not pulling on the knot to undo it when not loaded and I think the Fishermans is easier to check after tighten it.
This is just my own opinion. But are there other people out there who might think of a Zeppelin in a prusikloop or why is it nowhere mentioned as possibillity?
I could also imagine to use an alpine butterfly bend for a prusik loop...

Coding, have you obtained the answers to your questions?

If not; to re-emphasize...
1. Accessory cord is cheap. It is common to see climbers/canyoners/abseilers/cavers carrying several different lengths of 'prusik loops' (a pre-formed loop/circle).
2. It is normal to use #1415 (Double fishermans/Grapevine) as the end-to-end joining knot to form the loop/circle.
3. Yes, #1415 jams solid - but nobody generally cares because the intention is for permanence (ie to create a permanent 'prusik loop')
4. You can indeed use a Zeppelin as the end-to-end joining knot... the stiffness/hand of the cord plays an important role in how well you can cinch and dress the knot.
5. When using #1415, as Dan Lehman has pointed out, you can deliberately position the joining knot at the 'bridge' across the coils of the Prusik hitch. In this way, you limit the force on the knot so it will not have the same propensity to jam.

These days, you can also purchase 'bound' loops (sewn)...Sterling ropes USA come to mind.