Animated Knots was wrong 

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So 2 points of concern, and my belief of why these are generally not hitting their target strength. 1. After the rope is spliced through the other side, it is then bent back 180 degrees on itself for the bury. Theoretically this gives you a 1:1 bend rad, which Dyneema states is the min. to retain full strength, but realistically i don't believe it does. In all the illustrations i have seen in reference to the min. 1:1 bend radius, plus the verbiage used, the radius the rope is bent around is a rigid material, i.e. a steel shackle or pole, dyneema of course being quite a flexible and soft material can be scrunched up into a less than 1:1 ratio when another rope is constricted around it. So right there, is real loss of strength. 2. There is also the "throat angle" which is the measured distance from where the inside of the rope eye makes contact with what it's pulling against (in this case, the other end of the rope being spliced through and folded back on itself and then buried, the other eye, this loop is literally just two eye loops pulling against each other). Throat angles for dyneema are suppose to be a min of 3:1 and preferred 5:1 to retain max strength. This creates much less than 1:1. This is why i think you are getting less actual strength than what Animated Knots states. I'd bet they are getting the theoretical strength using roughly the same equation as a soft shackle, which is a bad idea since the eye of a soft shackle once pulled over the knot is probably pretty damn close to 3:1 throat angle. Now all of this is not to say a Grog Sling is a bad idea, you have to choose a rope thickness that will ultimately yield the safety margin needed for your application, so they can of course be super good enough. From a purist standpoint, bending the rope back on itself like it is here is scary af to me.

The "finger trap" quality of hollow braid Dynema is contingent on it being able to contract around the cordage inside if it. With the tails crossing, you have the Dynema trying to construct around a bulge. The only friction would be where the tails cross. Long but separate tails would provide the most friction.

I wonder if Animated Knots has a test facility, or they just regurgitate "known knowledge".

I noticed you used very shot tapers. My experience with Polyester and Dyneema tells me to use at least 1-1.5 fid length tapers or longer. I wonder if testing different taper lengths would have any effect. Given you failures were not consistently at the splice.

Hey Ryan, There’s a few things that I think are incorrect or misleading in this video that I want to point out. I did a lot of testing on grogs before sharing grogs, including using them on lines and 27 breaktests, and a lot of that information is mentioned in my article about them: (link redacted to appease youtube) I would really encourage anyone interested in grogs to read the article before forming an opinion about them. I include my break test results, the reasons for using grogs over other systems, and accurate instructions on making them. Onto my problems with the video: 1. For 5mm, you have tested ~2.5” buries, 6” buries, and 9” buries. The 2.5” buries slipped, just like the 2” bury I tested. The next you tested was 6”, which tested well but you say is too long. You didn’t test any intermediate sizes, and if you had you would’ve realized 4” (20x diameter) does just as well as 6” (30x diameter) while being a smaller, lighter sling. Particularly, it allows the loops in connections to be much closer without sacrificing strength. Your 6” and 9” buries all broke in the range of the 4” buries I tested. 2. On your blog, you list the “short” 5mm buries as 4” long, when it clearly states in the video they are 6-7 cm, which is roughly 2.5”. They are clearly not 4” long in the video. None of the grogs I tested at 4” slipped, nor did any of the 3”, only a 2” grog slipped. This is a serious mistake that makes a perfectly safe grog seem almost half as strong as it is. 3. You shouldn’t taper the tails of grogs. As they are sensitive primarily to bury length, this will only weaken them. Tapering the tails reduced the effective bury length, and may be why your 2.5” grog slipped at such a low value. A 45 degree angle cut is the proper tail finish for a grog, do not taper your grog tails. 4. Jake mentions inverting the sling to make it more secure. This is fine, it doesn’t change the strength significantly, but is also unnecessary. The tails do not come out during use, as we have tested at multiple festivals and 6+ month permarigs. 5. Double wrapping grogs works great. I haven’t had a chance to break test them yet, but they were used on almost every split rig at GGBY (except two lines that had single wrapped grogs, and one quicklink DLV). You can get just as close as with a soft shackle. One double wrapped 5mm grog is as light as a double wrapped 3mm soft shackle and roughly the size of a double wrapped 4mm soft shackle, while likely being stronger than each. There is no benefit to reducing diameter when double wrapping grogs, as you already have to make the 5mm grog longer than needed to fit most webbings, and the weight savings on double wrapped 4mm grogs are very negligible. 6. Naming this “Animated Knots is wrong” is highly misleading, and disrespectful to the person who created the grog (the website is run by Grog himself). Animated knots merely cited other testing that didn’t overlap with yours. Just because a reference they cited didn't get the same results as you doesn’t mean they were wrong. I posted something akin to this reply when the video came out, but included a link so it never posted. This above is what I responded to on SlackChat. I think it's important information for people learning about grogs through this.

Short bury, recommended bury, long bury... but no dingleberry.

Perhaps I've missed this: Has anyone tested "traditional" continuous loops, vs. grog loops? Say 3 of each, 1/8" amsteel blue, oriented the same way, in the same setup? For the test, I don't think you need to bother with the stitches on the traditional loops. (I do minimal stitches, just to keep the ends from pulling when the loop is not under tension; I always tension the loop before stitching, and use strong but "loose" stitches.)

Here's another method for making a dyneema loop that does not require the 180° bends for burying the ends that this method does: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9-4AYV7jKRA.html

I made one out of technora, and have been wanting to break it. This feels like you've read my mind! Also, the folks at Samson feel that the brummel is not worth it, and you should just splice the ends straight into each other followed by lock stitching. Is lock stitching a bit time consuming? Sure, but if the goal is to achieve max strength retention....

If you really want to feel like Ryan you gotta say it kilonewtents.

the sliding on the shackle is likely causing a local weak point from melting or abrasion.

I wonder if the loop sliding along the bolt towards one side has an effect? Could it be getting pinched in the gap between the bolt and shackle hole? You might consider using a spool to keep the loop in a more friendly position.

im curious, does stitching add any considerable amount of rating after making a grog loop? Or does that just make it something else?

I guess prudence dictates that this loop should be treated as 100% breaking strength? Still not bad considering the strength to bulk/weight ratio.

Just looking at these, are they mainly breaking around the green-pin. Have you tried wetting the line to see whether there is an effect (ie either cool or lubricate the fibres as they pull around.). The combination of diameter, applied load and rate of applied load might make a difference where it is bent round an anchor point working under load suck a lowering point or like a boat mooring bollard. Have you tried any of these tests using pulleys, like the Petzl pulleys? These might reduce the rate of increase in heat and friction set. Also have you tried a test on a virgin and heavily worked (ie hardened) piece of line. I read some where that they regain their strength after moderate deformation and cooling, but can hardness be an inspection control against serviceability. The same article was talking more about maintaining the sheath for UV screening and avoiding contamination. Great video again, keep it up.

I think you meant 60% total right? Reduced by (not to) 70%, meaning 30% x 2 = 60% total strength for the loop. I mean, imagine you just tie a bend (double fishermen’s, for example), the strength on a single strand would be 30%, but because it’s in a loop, the force is divided, so 60% total in the end. Doing the Brummell splice is similar to that, since the bend radius of the contact point in the joint is similar. Unless I misunderstood the animation, you are not splicing the end of one side to the other (which would maintain almost total strength), you’re splicing the end into itself after the locking Brummel. So, equivalent to a knot (but less prone to slip, since it’s dyneema).

Dyneema melts at 140 c and breaks lower if you pull it fast. Hmm, I wonder if Dyneema breaks higher when wet and pulled fast.

Woah anchors, dyneema, Amsteel, climbing, anchors. Send.

I am suspect of the breakages at the shackle. I think the shackle is compromising the rope. I'm wondering if a protective sleeve over the pin/shackle might alter the results.

maybe the reason they break more easily when you shock load them is that you pull on the tighter strands first and break them. it might just happen too fast for the slack to come out of all of the strands.

Seems like the reason it's not 180% is that it's not 2 eyes, but a brummel, which is kinda sorta somewhere like eyes through half of the other one.

Thank you Jake you're quite a mastermind, explained everything perfectly. I hope to see more of you on this channel

Watched so many of these break tests that the sound of the hydrologic is my tell to strength or weakness. Love the work you do, thank you!!

How do you know that the plastic is all the same. As in if it is made (the plastic) on a different run by the chemical plant. Seems like the plastic itself before it is made into rope is in question. Lets just say that one run of the chemical is contaminated or not heated the same way. Seems like the variables of the actual plastic needs to be looked at.

i think this is a dumb question but have you ever heard of someone making Amsteel loops to replace the sown slings on cams?

1:12 I feel like Ryan jinxx it's warm, got me😭😭

One thing I noticed, is that after the splice there is a really sharp turn, as from how it looks the end is buried on itself. Could it perhaps be a bit stronger if it were to be buried on the "other" strand? That might be one to test in the future. Obviously the caveat here would be that perhaps it would also be a lot weaker as the overall friction of the splice and fingerlock could also be less due to a more straight routing.

Would love to see the double wrapped grog tested here if it hasn't been already.

Could this splice be used to create new slings on cams?

I sure hope Ryan will sell soft shackles on his website

I wonder if the amsteel wedging into the metal shackle/bolt interface is causing it to fail a little early

1:15 the splice nominally has 70% efficiency, the loop is doubled such that one side is spliced and the other is not. you assumed 70%+70%=140%, but i think that would actually be representative of a loop with two splices, one on each side of the loop. for a loop with one splice, i would expect 70% (spliced side) + 100% (unspliced side) = 170%, which seems closer to your real world results. cheers!

No need to have a dog in the fight.

I30 to 150%. I may be crazy here, looking at statistics, if you have two uncorrelated functions of equal whatever, their combined strength is diagrammed at right angles because they are un correlated. a little math here courtesy of Pythagoras. A 1x1 right angle has a hypotenuse of the square root to 2 or about 1.4142+ which puts it right in the middle of your results. Is this an ah-ha moment or an aw-shucks moment? Changing the subject, bury lengths are sensitive to the coefficient of friction, and Amsteel's is a lot closer to teflon than nylon. Dyneema is different, not merely better.

Very interesting knot test. Could you please test the difference between tying double stopper knot vs European death knot. As they are both used for tying two 60m ropes together in order to do a long rappel. I'm a climbing guide and have had many people ask me to use the other one however no once can successfully tell which knot is safer to use on rappel.

Hey ryan inwas watching your climbing gear porn video and noticed your link cams or as you like to call them ur oh shit cams was wondering if you were ever going to do a break test on them Ps love the videos keep up the great work

Everything I know about splicing tells me that your buries and tails are way too short. Dyneema is so slippery that you need long buries to spread the friction across the tail. Also short tapers are stress concentrators, so it's not surprising that it will break there. Caveat that all my experience is on boats where it's very common, but we mostly only do eyes and soft shackles.

Have you looked at/tested other splicing methods? This one seems interesting. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-fkuMtmP95f4.html

We use this splice-technic on ropes that be used to start a sailplane/gilder on a winch. We had never any problems with that splices. The Load is always static on slow acceleration. (We splice every ropeend with 0.5 meter into the other ropeend)

Have you ever tested the finish of the shackle? The zinc plated finish is rough, try polished steel after removing the zinc by soaking in vinegar.

This seems like it might be a way to replace old cam webbing……no ?

Why not do like an Ouroboros type splice that loops around 3 or 4 times?

I see the same amount of dyneema touching the shackle, looped or not. That is where it appears the load is transferred through. It's braided, so the load gets put through individual stands differently depending on how they lay in the braid on the shackle. This could be why some stands are hanging out long after breaking. Maybe? Or not...

if you stick the end through the other rope to double the strenght, is't the outer just a sleve (chafe)over the centre rope

Great video. As I understand it, assuming the particular "backwards" brummel is 70% efficient, a loop should have 170% of the rope's breaking strength. Jake I think wrongly assumed that the 30% loss applies to both sides of the loop making a theoretical 140% but the strength loss only applies to one side of the loop. Not sure where 180% comes from, maybe AN's data showed 80% efficiency of the brummel? "The Effect of Bending on the Tensile Strength of Statically Loaded Synthetic Ropes" by Mark Pederson, Greg Mozsgai and Danielle Stenvers, is a great pdf to scroll through, particularly slide 14. Also of note, the "closed off side" of the brummel can be opened up enough if you flip the brummel to have the bury go straight into the already created hole. Wonder if this has a significant effect on the splice's strength as opposed to jumping over a few strands as shown in the video. TL;DR: Sling strength should theoretically be 100% + splice efficiency%. I wonder if you could isolate the variable of the loop and instead join two separate lengths together with the "backwards" brummel splice to get more accurate data on the splice efficiency.

Спасибо за ваш труд

So I noticed the tails in the loop were oriented crossing away from each other. Burying into themselves more or less after the Brummel splice. Isn't there a way to make the Brummel or another ring splice where the tails continue in line so you don't have the hard 180 bend?

Big question tho: is he tapering his tails or are they just cut square and called good enough? It's those "sharp' bends that get you every time

Do you recognize that you only have one strand at the carabiner? I think your estimate of doubling the strength for two strands is off -- yes you only have 50% of the load applied on each strand going between the 'biners, but at the 'biner you have 100% of the load applied to a single strand (and it is applied at a sharp bend instead of straight pull). The only surprise here is that it wasn't failing at the 'biner every time.

With the nut on it didn't slip on that shackle, unlike the prior tests without the nut which always seemed to slip?

Bro, you’re killin me. Shackles have a pin and they have a saddle. Put the smaller side in the saddle so it stops moving on the pin and towards to hole.