Author Topic: To Daisy or not to Daisy  (Read 1701 times)

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Offline KevinW

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To Daisy or not to Daisy
« on: May 01, 2009, 09:19:49 am »
Consider this post as informative/food-for-thought, rather then me trying to make a point or start a debate, because..

My eyes are crossed from from reading 7 pages of debate on the use of daisies over at rc.com, where in typical fashion the banter degenerates into personal attacks etc.
When daisies first came out I thought they were a great idea, but a particular case file in the ACC accident database (which has been inaccessible for months now, for some reason) made me think twice about how and where I use daisies.

The scenario involved two climbers at an anchor, one clipped in using his rope and a clove-hitch, the other via a daisy. The ledge they were on unexpectedly gave way, both climbers dropped- ripping out the anchor and plunged to their deaths. The analysis concluded that the climber attached via a daisy, (who also had two loaded packs resting on the ledge, attached with a sling to the anchor) had shock loaded the anchor to the point of failure. The recommendation was to always clip the anchor using your rope or other anchoring system that possesses dynamic properties.

I came across various articles where specific testing had been done on attaching oneself to the anchor with slings, cow-tails, lanyards, etc. and was suprised to learn how much force could be generated in what one would consider more of a *slip* then a fall. The more I read, the less I clipped my daisies. Considering that aid climbers spend more time hanging from (and depending on) marginal pro then most, I re-thought my technique and went back to using dynamic cow-tails as I had in the pre-daisy era, rationalizing that the more shock absorbing components in my system the better.

It's to each his own, but here's something to consider:

-A fall of less than one meter on static sling can create a shock load above 15 kN.

As it turns out, cow-tails had a bit of bum rap in they past due to improper/inconsistent methods of testing. It turns out that the "knot" was crucial to the shock absorbing properties of the system.
-with knotted cow-tails, "the knots" introduce a greater amount of shock absorption into the system then the dynamic properties of the rope used to make them

There are a few methods of constructing cow-tails, the most common being to tie one end into your harness as you would your rope and the other to a biner using a "half a double fisherman's" sometimes called a barrel knot.
Not only does this knot have exceptional shock absorbing properties, but properly choked, it can prevent cross-loading of the biner.
Some construct cow-tails using a barrel knot & biner at both ends.

Here's a couple article with test results you may find interesting:

There's many test results of all sorts in this document, but the part pertaining to, "ATTACHMENT LANYARDS (Cow?s tails)" starts on pg. 79 Section 7.1
http://www.hse.gov.uk/research/crr_pdf/2001/crr01364.pdf

This IRATA document is specific to lanyards
http://www.irata.org/pdf_word/lanyardtest.pdf


Offline Caz

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Re: To Daisy or not to Daisy
« Reply #1 on: May 01, 2009, 10:33:14 am »
How about use this.




or these

I do this for fun...

Offline Rags

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Re: To Daisy or not to Daisy
« Reply #2 on: May 01, 2009, 11:00:40 am »
Kev, that's all good info. I do appreciate a good debate that informs of technical issues involved, but I have to laugh.

Quote
My eyes are crossed from from reading 7 pages of debate on the use of daisies over at rc.com

Are we experiencing RC overflow here? Just joking...

You are correct about all the issues of slings/daisies and shock loads. Tying in to any anchor with the rope is best. Clove hitches are sufficient, they slip around 1,000 lbs.

Shock loads while clipping in with daisies can be avoided by keeping short as possible, clipping intermediate loops where stitches will rip, or just keeping tension on them so there is no shock. Or, has been shown use screemers.

There really is no debate, use'em in an informed manner, choose to use'em any way you want and assume your own risks.

P.S. Mini rant....   this is the basic kind of info that boggles my mind. I'm boggled by how so many climbers send their asses up on cliffs absolutley ignorant of their gear and it's limits. Climbers place their lives on the line, trusting shit they have no clue about to keep them safe, never spending on second learning about it BEFORE they go up. Oh well, Darwin would have a field day studying climbers. End rant......

Kev, I'm glad your not in the study :)
Be Safe, Live Long, Climb Hard!

Rick

Offline KevinW

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Re: To Daisy or not to Daisy
« Reply #3 on: May 01, 2009, 12:04:49 pm »
Those will work Caz, (love those Yates shorty's btw).

Good points Rags, and I couldn't agree more with your mini rant, which reminds me of a recent encounter that relates to this topic.

I was watching a couple of young dudes as they were worked on their aid technique, with plans of heading to the valley in a few weeks. One was using cow tails clipped to his aiders, the other daisies.
They were obviously pretty green, I think the valley was going to be their first attempt at multi-pitch aid, one of them may have done a little in Sqeemish, I forget now, I did talk to them about it though.
I watched the dude with daisies clipping his way under a small roof, I was about 10' to his right, and asked him if he always used his daises like that. I'm not sure if it was because he was nervous-in-the-service
at that moment, but  he glared, then snapped at me, basically telling me to mind my own business. It had been a perfect opportunity with the nice big loops his daisies were forming as he was clipping, to
point out the potential shock load on his next piece if a piece he was clipping pulled, not to mention the probable subsequent zipper. But hey.. who am I? and so I minded my own business.

Later I was on the ground talking to the other one and asked him if his cow tails were made from static cord, (they looked suspiciously like the local off-the-roll stuff) to which he replied,
 "no way man, I don't want to shock load my pro"
We continued watching the daisy dude clip away and he added, "ya.. he just doesn't get that".
What could I say other then "oh he will " to which the dude laughed his ass off.

The dude that snubbed me continued to do the same little crack over-and-over for as long as I was there, running laps, changing/learning nothing.
The last I saw of the cow tail dude, Brenden was teaching him how to hook, and (I think..) explaining why he should ditch his alpine aiders and pick up a set of ladders.
One of these guys will definitely be a Darwin award candidate, while the other will most likely become a very competent climber.

Offline Rags

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Re: To Daisy or not to Daisy
« Reply #4 on: May 01, 2009, 11:05:10 pm »
Nice tale, no pun intended.
Be Safe, Live Long, Climb Hard!

Rick