C.A.M.P. Daisy Chain Twist


Original Post
delly84 · · Golden, Co · Joined Jun 2013 · Points: 64

Alex Temus wrote:

Because of the whole "Daisy chains should never be used for falls" scenario we always find ourselves in, I was pretty impressed to find the C.A.M.P. daisy that is good for 22kN on every loop!

I bought one a few weeks ago, and even though I still try to avoid a scenario like that, I like that it gives me a bit of peace of mind. It's basically a non-issue now.

http://www.campsaver.com/c-a-m-p-daisy-chain-twist

C.A.M.P. Daisy Chain Twist Details

The spiral construction of the Camp Daisy Chain Twist addresses one of the main concerns with traditional daisy chains where the user clips a single carabiner through two loops creating a situation where they are secured by nothing more than the single bar tack between the loops instead of the 22 kN strength of the entire loop. Robust 16 mm polyester construction with special machine-driven bar tacks distribute the load multi directionally.

i'm not sure i understand the concept of that camp daisy. so the point is that there is a twist so if you clip two loops to shorten it you're not being held in by just bar tacks. 

...but it seems like that only applies to skipping an even number of loops. if you skip an odd number of loops you're still only clipped in with bar tacks ... right?

C Runyan · · Boulder, CO · Joined Jun 2006 · Points: 300

Odd, even,  makes no difference. 

Look closely at the daisy. Each separate bar tacked section sprials around the main body of the cord. So as I understand it, if your biner is connected to the main point and then also clipped in at the first bar tack section, a failure of the bar tack would result in the daisy still clipped into your carabiner, only with an extra loop of webbing around the biner. If you blew out two bar tacks (if you are connected to the main point and the second bar tack section) you would end up with two loops of the daisy wrapped around your carabiner -- but still clipped in. And so forth.  

delly84 · · Golden, Co · Joined Jun 2013 · Points: 64
C Runyan wrote:

Odd, even,  makes no difference. 

Look closely at the daisy. Each separate bar tacked section sprials around the main body of the cord. So as I understand it, if your biner is connected to the main point and then also clipped in at the first bar tack section, a failure of the bar tack would result in the daisy still clipped into your carabiner, only with an extra loop of webbing around the biner. If you blew out two bar tacks (if you are connected to the main point and the second bar tack section) you would end up with two loops of the daisy wrapped around your carabiner -- but still clipped in. And so forth.  

i see what you're saying but i'm not sure i agree with you. 

so if each loop is numbered from 1 to n loops, if you clip 1 and 3, skip 2 and clip that into the clip in point, it looks like you're only tied in with bar tacks.

C Runyan · · Boulder, CO · Joined Jun 2006 · Points: 300

Not convinced, then try it. Simulate the daisy chain twist by taping a piece of regular webbing in place of bar tacks. If you spiral each loop in the same, continuous direction a full loop around the main body of webbing, clipping any two loops is not an issue when the tape/bar tacks fail. 

Edit: Ah, beat me to the punch, with clear visuals, too.

dino74 · · Unknown Hometown · Joined Sep 2016 · Points: 10

I think delly is right. I thought they continuously wrapped the webbing in the same direction, I didn't realize they alternated the wraps direction. Appears that you must not connect even to even or odd to odd. Hmm

C Runyan · · Boulder, CO · Joined Jun 2006 · Points: 300

Oh my god, I stand entirely corrected. I can't believe anyone would create such a useless piece of junk with the loops alternating, not spiralling. Why create this kind of product? Sorry for the confusion. 

dino74 · · Unknown Hometown · Joined Sep 2016 · Points: 10

If you connect the two outer loops and then tear the four stitches between them, the carabiner will come off.

Gunkiemike · · Unknown Hometown · Joined Jul 2009 · Points: 1,875
dino74 wrote:

If you connect the two outer loops and then tear the four stitches between them, the carabiner will come off.

Gunkiemike · · Unknown Hometown · Joined Jul 2009 · Points: 1,875

While I agree that they could have done a better job design-wise, tearing even-to-even means ripping EIGHT bar tacks.

Kevin Mokracek · · Burbank · Joined Apr 2012 · Points: 50

Oh my gawd!!!!!

Nate Doyle · · Unknown Hometown · Joined Feb 2016 · Points: 0
Gunkiemike wrote:

While I agree that they could have done a better job design-wise, tearing even-to-even means ripping EIGHT bar tacks.

In theory and assuming the webbing itself held, does this mean it would require 44kn to rip apart since it's doubled up? Or would it only require 22kn to rip through all eight bar tacks?

The Grivel Daisy Chain below is rated to 23kn. Aside from the 1kn difference (or 2kn difference if doubled up?), how would it be any different from a 22kn rated Twist? I mean, I feel safer with the Givel but, we are talking about almost 5000lbf, are we not? Isn't that roughly the same amount a bolt is supposed to hold?

Also, I guess I'm trying to understand how it would rip through the front-side bar tacks and then the force would be somehow applied to the back-side. I mean, some of the force is going to be distributed upwards onto the the rest of the webbing itself as well as onto the bar tacks directly above the carabiner.

ETA:

I'm assuming by their sales copy that each loop is rated at 22kn. You know what they say about assumptions. I'll contact CAMP to verify this. Stay tuned...

20 kN · · Hawaii · Joined Feb 2009 · Points: 1,128
Nate Doyle wrote:

In theory and assuming the webbing itself held, does this mean it would require 44kn to rip apart since it's doubled up? Or would it only require 22kn to rip through all eight bar tacks?

The Grivel Daisy Chain below is rated to 23kn. Aside from the 1kn difference (or 2kn difference if doubled up?), how would it be any different from a 22kn rated Twist? I mean, I feel safer with the Givel but, we are talking about almost 5000lbf, are we not? Isn't that roughly the same amount a bolt is supposed to hold?

Also, I guess I'm trying to understand how it would rip through the front-side bar tacks and then the force would be somehow applied to the back-side. I mean, some of the force is going to be distributed upwards onto the the rest of the webbing itself as well as onto the bar tacks directly above the carabiner.

ETA:

I'm assuming by their sales copy that each loop is rated at 22kn. You know what they say about assumptions. I'll contact CAMP to verify this. Stay tuned...

The loops are not each rated to 22kN. There is no way two 5/8" single pass bar tacks can hold anywhere near 22kN. The 22kN rating is likely end to end, and not girth hitched in a loop like in the video above, but pulled end-to-end in carabiners or a webbing drum. In other words, the only way it's holding 22kN is if you use it as a runner or something of the sorts, and you clip into the last loop.

Gunkiemike wrote:

While I agree that they could have done a better job design-wise, tearing even-to-even means ripping EIGHT bar tacks.

It's a bit more complicated than that. While there are eight tacks between two loops, only two of them are loaded at a time which means if the force is high enough to rip two then it could rip all eight from a lack of equalization. It's called cascade failure. Below is a good example:

I would view that thing as not much different than a traditional daisy. Unless you're using a PAS of sorts with fully sewn loops, dont clip into two loops at once.

Gunkiemike · · Unknown Hometown · Joined Jul 2009 · Points: 1,875

I never suggested that all 8 bartacks would be loaded (or need to fail) simultaneously.

And cascade failure of bartacks is not a given.  It is quite possible to bust a few but not all.  Case in point - partially blown Screamers. Not that uncommon.

Michael Schneider · · Unknown Hometown · Joined Apr 2014 · Points: 85
Gunkiemike wrote:

I never suggested that all 8 bartacks would be loaded (or need to fail) simultaneously.

And cascade failure of bartacks is not a given.  It is quite possible to bust a few but not all.  Case in point - partially blown Screamers. Not that uncommon.

Mike, check it out !

https://www.mountainproject.com/forum/topic/113182931/gunks-partner-tuesday-620#ForumMessage-113184386

dino74 · · Unknown Hometown · Joined Sep 2016 · Points: 10

I'm assuming by their sales copy that each loop is rated at 22kn. You know what they say about assumptions. I'll contact CAMP to verify this. Stay tuned...

I believe each loop's rating is somewhere in the 2-3kn range but I'm not100% sure.

Nate Doyle · · Unknown Hometown · Joined Feb 2016 · Points: 0
dino74 wrote:

I believe each loop's rating is somewhere in the 2-3kn range but I'm not100% sure.

Supposedly, normal daisy chain loops are 3kn. That's what is suggested in the Grivel video, at least. They seem to be suggesting 1 bar tack on those but, that may be for the convenience of tapping/velcroing for demonstration purposes. The BD Daisy Chains I've seen and the one currently on their site have two bar tacks for each loop. Not sure about other brands.

Waiting to hear back from CAMP on this.

Nate Doyle · · Unknown Hometown · Joined Feb 2016 · Points: 0
Goran Lynch · · Oakland, CA · Joined Jul 2008 · Points: 3

The product description is, taken with a literal interpretation of "two adjacent loops", true: 

(taken from http://www.camp-usa.com/products/webbing/daisy-twist/)

"The spiral construction of the Daisy Chain Twist addresses one of the main concerns with traditional daisy chains where the user clips a single carabiner through two adjacent loops creating a situation where they are secured by nothing more than the single bar tack between the loops instead of the 22 kN strength of the entire loop."

... but why don't they just continuously spiral the pockets?! This seems bizarre, and the description+construction as-is sure seem misleading, if not outright false. That said, Jonathon at CAMP has been outstanding in supporting CAMP products for me in the past so I'm inclined to give him/CAMP benefit of the doubt that there's may be a good reason not to build an actual twisting daisy chain. 

CAMP, it seems like y'all are watching. Any word?

Goran Lynch · · Oakland, CA · Joined Jul 2008 · Points: 3

Well, CAMP exceeded all expectations and sent me a comprehensive email describing the genesis of the daisy chain that is the topic of this thread. Jonathon gave me the OK to post our correspondence. 

Pretty impressive.

---

Hi Jonathon,

You've handled situations with me in the past kindly and honestly, and I wanted to give you a heads-up that your correspondence regarding daisy chains is the subject of an ongoing MP thread (my contribution included):

[this thread]

I think the community at large would appreciate understanding why the "twist" daisy chain is not built in what would seem to be the natural way, making a connection between any two pockets full-strength. Unless I'm mistaken, a daisy chain in which twists occurred continuously would actually achieve this goal; the CAMP twist chain appears to twist every other pocket. 

To be clear, I agree with you that daisy chains are not the right tool for anchoring, etc, and I only use them for direct aid. That said, the product description indicates that the "twist" chain solves a general daisy chain risk when, in fact, it doesn't (though as I pointed out on MP, the product description taken literally is accurate).

Thanks again for your input,

Goran

---

Hey Goran,

The testing and certification process for Daisy Chains is very specific. It requires a certain number of loops to pull out to absorb energy to become full strength, only when the daisy chain is fully open end-to-end. The Daisy Twist is designed specifically to meet the requirements for the Daisy Chain certification process.

We originally conceived the Daisy Twist in the manner you suggested. We built and used prototypes with the webbing spiraled around the main length and loved it. For us, the biggest benefit is that the loops stay open better and longer than standard constructed loops (which tend to sag over time with repeated heavy use). If the loop side of the webbing is spiraled around the straight length of webbing, the strength of the individual loops becomes stronger than the certification requires. With this increased strength, this stops enough of the individual loops from blowing out during the testing process; yet, at the same time this spiral construction method is not stout enough to individually certify each loop at 22Kn; so we could not use it to create a PAS-type product. 

Any time two intermediate loops of any daisy chain are clipped together; it is being used incorrectly, regardless of whether they are adjacent to one another or separated by one or more loops. Daisy chains are intended to have one intermediate loop clipped, to adjust for length, along with the final loop. This is the only appropriate way to use a daisy chain. The danger of cross clipping two adjacent loops in a standard daisy chain is real – Generating 2-3Kn is relatively easy with a short, semi-static daisy chain fall. Generating the force required to pull the 4 double-bar tacks that create the three loops of the Daisy Twist, in the scenario described previously, is much harder. In fact, it is almost impossible for a single person to generate this amount of force in a worst case scenario daisy-whip fall. 

I hope this is helpful. Let me know if questions come up.

Happy Climbing,

Jonathon

---

[from me]

Thank you for getting back to me! Just so I understand correctly, the "full twist" prototypes were actually too strong and did not rip out enough pockets to meet a shock-absorbing component of the daisy chain spec? This implies that the eventually released "half twist" design (i.e. the one for sale) actually has pockets rip more easily, which is intentional.
Do I have that right?

---

[from Jonathon]

You have it correct. The full twist prototypes were stronger than the Daisy Chain certification required which prevented the bar tacks, on a series of loops, from tearing away during the shock absorption test. While each loop did come out  stronger, they were not 22kN each, so we were unable to create a PAS from the design.

eli poss · · Durango, Co · Joined May 2014 · Points: 136

So the better product didn't meet the standards even though it was better than the standards, and so they couldn't sell it? Gotta love bureaucracy 

Christopher Woodall · · Somerville, MA · Joined May 2015 · Points: 13
eli poss wrote:

So the better product didn't meet the standards even though it was better than the standards, and so they couldn't sell it? Gotta love bureaucracy 

To be fair the actual issue was that their product wasn't good enough to qualify as a PAS type product thus it needed a dynamic failure mechanism required by a daisy type product. Since their product was too strong to reliably fail dynamically when used properly (breaking stitches) but not strong enough to guarantee the stitches wouldn't break to the standard of a PAS (each loop fully rated) they needed to derate the stitches. From an engineering perspective this is the right thing to do, otherwise you would be selling a product that couldn't be safely used as a daisy or a PAS, so it would just be a dangerous POS.

Guideline #1: Don't be a jerk.

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