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Thoughts on Girth Hitch Equalisation
John Tuttlewrote: Given how much you've harped on good placements as being the most important part of an anchor (and I agree), don't you think that it undercuts your argument to advocate for using a method (death triangle) that effectually makes each placement weaker? Or do you want strong placements because you want to use an inferior system that artificially requires each piece to be stronger than it would need to be with any other system of attachment? I also don't see how what you're doing is any more minimal than what Glowering is doing... unless of course, you're talking about minimizing anchor strength and not minimizing the amount of stuff you bring. And I don't see an ADT in Marks pic either. |
John Tuttlewrote: Wait, you said using the rope save FAR more force, now you're saying it's a small increase LOL. Again an ADT is fine on two bolts, but why use something inferior at all? I'd rather do it like your first photo with an 8 masterpoint on the bottom and eliminate the issue. I'd rather use a better option all the time, so if for example it's dark and I'm dehydrated and I'm not thinking clearly and I'm using two cams I don't use something that could cause an issue. But that's just me.
Pretty much every source I see says don't use an ADT.
A double length sling is not specialized gear. I can use it if the route changes direction to avoid rope drag (then I'd use the rope in the anchor) and I use it as my tether if I'm rapping.
You're not wrong. But your way isn't better than other ways. Except I wouldn't use an ADT when there's better methods available.
That's wouldn't become an ADT. And ADT has a strand or rope/webbing going horizontally across the top of the triangle. And I don't care who the climber is, I'm making decisions about what methods I use based on my own reasoning and experience (and testing new methods I hear about to see if I like them). |
Gloweringwrote: You don't understand what an ADT actually is. An "ADT is any suspension between two spaced points (like a highline is the ultimate example). If the center piece fails then the two widely spaced pieces on either side become the support for the triangle at nearly 90 degrees in this case. If you take a look at the info out there that utterly debunks worries about the "ADT" the fact of the matter is that the forces are minimally increased and any modern gear is more than capable of holding it....or every highliner would be dead. Use w/e you want man. People with experience are over this pearl clutching worry about something that is not an issue. It's been debunked. |
Brandon Rwrote: Good placements negate any requirement to "equalize forces" AND it is clearly established that equalization is a myth anyways. You also don't understand the physical characteristics that create an "ADT". See the post above. Pearl clutch all you want about suspending body weight or even hauling on an "ADT". I refuse to worry about debunked nonsense. There is only one kind of placement, a good one for that type of gear/hardware, and in reality, whether using an "ADT or not, only one of the pieces will bear all the force as equalization is a myth. THAT is why you need strong placements. ADTs remain out of fashion because you are effectively using one sling with no redundancy. I don't recommend slings for that, but the rope is more than good enough. Other than that, there is nothing wrong about one big Figure 8 on closely spaced bolts for fixing a rope or belaying a second. Nothing. You are just blindly clinging to current dogma. |
John Tuttlewrote: You're using a different definition for American Death Triangle than every other person in this discussion. I doubt you're unaware of that, I think you just backed yourself into a corner with your claims that now your only option is to Jordan Peterson your way out.  It even has its own Wikipedia article: https://en.wikipedia.org/wiki/American_death_triangle |
John Tuttlewrote: I think it's actually you that doesn't understand the difference in the two anchors below. And I didn't mention anything about "equalized forces" so save me the straw man argument. The fact is, the ADT, in addition to not being redundant, puts a not-insignificant increased force on each placement when compared to a "V" shaped anchor. It's not dogma, it's not nonsense, it's just fact. If you want to purposely, and for seemingly no good reason, continue to subject your pieces to more force than necessary though, who am I to stop you. I would caution people who read your (and your former MP monikers) recommendations to do so with skepticism, however.  |
John Tuttlewrote: Oh, the old two pointed triangle. P.S. from the photos posted above you can see why an ADT would be a VERY bad idea with two cams. The force is directed at angle between the two cams and the powerpoint, pulling the cams inward (which could be a big problem depending on the placements and the flexibility of the cams). Bolt hangers and proper bolt placement is also meant for a downward pull, but again they are usually so bomber it's not a big deal, probably at worst the hanger would twist inwards. |
Gloweringwrote: If you remove the parts of the ADT that aren't a problem you are left with what is essentially a highline. The problem isn't the two strands coming down to the master point, it's the taught bit up top acting as a large moment arm. Hillbilly is right. |
Ricky Harlinewrote: That's not what Hillbilly said and he is not right LOL. He showed an anchor (Mark's) without the horizontal line up top, that has a V at the bottom and said THAT is an ADT. Earlier he did show his anchors with the line on top, an actual ADT. No climber puts a taught length of webbing or rope between two horizontally opposed pieces and attaches their tie in to the middle of it. That's what you HAVE to do when you setup a highline/slackline and the forces are WAY higher. I've setup highlines and they need to be WAY more bomber than a climbing anchor. Using an ADT kind of transforms an anchor with a V at the bottom, partially into an anchor similar to a highline THAT is the problem. Here's a typical highline anchor.  Having your anchor points at a large angle at the bottom is a bad idea even with a V anchor but the ADT makes it even worse.  For Mark's anchor if the middle piece blows the masterpoint angle to the remaining two pieces is about 90 degrees. As Mark built it that's 71% of the force on each anchor (it wouldn't be equalized, but each leg would be under 100%) while an ADT would put 130% of the force on each anchor. THAT'S why I never use an ADT.  |
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@ Glowering I have a question, no criticiscm intended, genuine curiosity. For a highline anchor, where the forces are higher, is there any concern about the bolts pictures above being too close? Or is that super bomber good enough? If that rock around one of those bolts failed, would it compromise the other bolts, or is that so unlikely to essentially not be a concern? Also, if you did space out the bolts a little more, would that introduce too much of an angle? Are highline anchors ever constructed with well-spaced in-line bolts? Thnx. |
Bruno Schullwrote: That's not my anchor, that's just the first picture that came up in a google search for highline anchors. But I've put in a fair amount of bolts. And the first thing I look at is how solid the rock is in the area. That actually looks pretty chossy LOL. If the rock is all solid granite and a bolt failed (it would likely be due to shearing / failure of the bolts itself) I doubt it would compromise another bolt over 6" away. In rock that looks like the photo personally I would space the bolts out more parrelel to the highline (some bolts would be where they are and some would be farther to the right in the photo, inline like you mention) I wouldn't spread them out at a right angle to the line (sideways) and introduce more of an angle. |
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Thanks Glowering, that makes sense. |
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one of these days I'm gonna learn to read |
Your diagram above and comments seem to be disingenuous or maybe it's just your reading comprehension. 1. If Mark's haul anchor fails, the angles of the moment arms are there whereas you denied them previously. In addition, my anchor example has far narrower angles, and yet you take exception for belaying a second? My angles would be less far less than this yet you maintain this is safer? And we are talking about maybe twice body weight at most in my example whereas this anchor would have higher forces when hauling or in a failure as there is a drop of 2-3 feet before it would come tight again with the haul bag and the climber if anything pops. For the record, this is standard big wall anchor that Mark has built and I don't have any trouble with any of it. 2. In your diagram above, a Cordellette, Quad or other is not a perfect sliding anchor like you have shown and any force as much as a few degrees off of the ideal greatly concentrates the forces if not 100% on one piece. Then, the dynamic nature of using the rope (in any configuration) reduces the forces BY FAR in a LEADER FALL. Using your number of 60% then when the angle is less than 60 degrees (like mine which is closer to 30 degrees and will be very close to just 100% on each piece and which does not remotely concern me) the total reduction is from up to 60% (depending on the actual direction of the force which we cannot predict perfectly) whereas the static cord of a cordellette or static webbing is 100% on one of the pieces if you had forces applied with the tiniest of variance from perfect which is essentially always. 3. Using dynamic cord in the anchor that reduces forces of a max impact (7-9KN) up to 60% is a BY FAR reduction. That's ~1000+lbs reduction. Look dude, I get it that your dogma makes you focus on the past and you don't want to acknoledge current data debunking concerns about forces generated by the "ADT". Fact of the matter when it comes to climbing forces is that a cordellette from static material focuses more force on one piece as compared to when you tie in with the rope because the load bearing is always on one piece only with a cordellette. A quad might be slightly better but I would give up climbing before such nubbery became part of my quiver. The "ADT" myth that somehow "ur gonna die" if you use one has been thoroughly debunked. If you really grasp that equalization is a myth you will spend way less time fussing over your anchor and just do w/e you think is tidy and works for you. |
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John Tuttlewrote: Your diagram above and comments seem to be disingenuous or maybe it's just your reading comprehension Maybe I’ll read your latest comments and respond later but a quick glance shows you are claiming I said things I never said. |
Gloweringwrote: Ok, if that's how you interpret it then you have my sincere apologies. I honestly regret when these discussions turn prickly. Let's focus on the most important things in my opinion: 1. In the example I provided for belaying a second with one large figure 8 between two close bolts any additional forces from this narrow angle "ADT" are more than made up for by dynamic materials. Regardless, the forces are all negligible regardless of method for belaying a second off the anchor. Strong placements are all that is required. Virtually any redundant connection with proper knots (ie figure 8 etc not just simple knots that no climber would use) connecting strong placements with dynamic materials is perfectly safe as demonstrated by lab testing. There is no magical huge amplification of forces that make a reasonable angle ADT unsafe per se other than one static sling never being recommended. Redundancy of slings or the climbing rope by itself is required, imo. 2. For belaying the leader, dynamic connections as much as is practical are superior for energy absorption. All connections should be redundant. If you belay off of an adjustable tether it should incorporate dynamic materials and the connection to the anchor should be redundant (ie a secondary tie in for safety as FF2 forces on these tethers can be dangerous). No method (even sliding X's) will equalize forces on the anchor. Strong placements and redundancy are essential to your safety. Expect one anchor point to bear all the load. 3. Static slings (of any configuration) do not equalize forces as perfect leg length, orientation and perfect tightness of the legs is not achievable in the widely varying conditions of belaying a leader or follower. Dynamic materials are superior for building anchors to reduce forces. That's it from my perspective. Flame on. |
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I mean like I survived unequalized anchors for years so you should too. I'm surprised nobody has suggested a simple quickdraw on a Totem since they are sooooo bomber. |
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I love that this guy is on a one-man crusade to revive the American Death Triangle. This kind of shit is why I come to the MP forums. |
Ricky Harlinewrote: There is no "moment arm" at work in an ADT (or any climbing anchor made from soft goods). A moment arm is a body with rigidity that converts a force into a torque. Due to all of the materials used in anchors being flexible, and therefore only capable of transferring loads in tension, they cannot act as moment arms.* An ADT has a variety of problems, and 99.9% of people are aware that it's not a best practice, but it is not creating moment arms. (* the bolt hanger itself can act as a slight moment arm, but that's not really relevant or the context here, just want to make sure people don't think I'm glossing over that). https://en.wikipedia.org/wiki/Torque
Using a short piece of climbing rope in the anchor will not reduce the force of a FF2 fall by "up to 60%" or "1000+ pounds." This claim is erroneous, and not backed up by any math or test data. Non-dorky version: Adding another 1-2 ft of rope to a system that already has 8 ft (e.g. UIAA test fall) in it isn't going to reduce the force by more than half, that doesn't make sense. Dorky version: As a hypothetical model, let's assume an anchor constructed with a single strand of rope 0.5m long holding the belay device, and the leader takes the UIAA test fall (4.8m fall on 2.5m of rope). The additional dynamic rope in the anchor will reduce the fall factor from FF1.9 to FF1.6 (4.8/(2.5+0.5)). The spring rate of the longer rope system is ~83% of the shorter system. The relationship between max force with a fixed falling distance (energy) and variable spring rate is proportional to the square root of the spring rate, so the force reduction is roughly sqrt(0.83) or ~91%. In other words, 9% lower peak force. This is a pretty far cry from the claimed 60%. In real systems it's probably even less than this, because anchors are usually 2 pieces of rope to the masterpoint (twice as stiff), and there are additional dynamics that make rope effects less than 100% of the total system. |
Eric Craig wrote: DMM video: https://youtu.be/Vrgadjo9niY?si=qhLaCAMUWp_tLlnz This video has caused a lot of confusion and misinformation over the years. It presents large falls with a completely static mass (steel weight) and no dynamic connection whatsoever. It is not representative of real climbing scenarios, as leader falls involve a length of dynamic rope, and personal tether falls involve a squishy human. There's a discussion of how it's been misleading here: https://youtu.be/Fh30kHXfVm4?si=YTQuM8oV2wFsgkhD HowNot2 took some (shorter) human falls onto static slings and the forces were like 2 kN: https://youtu.be/nr3YBDnOI8Q?si=VvtkDJtHrZM8-Wdr&t=692 |
