Advice please on anchors

If you are a beginner climber and want to ask other climbers any questions - then this is the place to ask.
Simpi27
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Advice please on anchors

Post by Simpi27 »

Howzit I'm looking for some advice on making your own slings/ anchors from rope. I've got an 10mm rope. So my question is do I tie a figure of 8 or a double fisherman's so that I have an anchor?
I'm a beginner so hope I'm making sense?


deSouzaFrank
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Re: Advice please on anchors

Post by deSouzaFrank »

Deleted my original post here. Too long winded and I misunderstood your question Simpi.
So as SNORT says here below.
Last edited by deSouzaFrank on Sun Jan 23, 2022 10:13 pm, edited 1 time in total.
SNORT
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Re: Advice please on anchors

Post by SNORT »

There is a short answer to your question. A double fisherman's aligns the rope best for a sling!
deSouzaFrank
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Re: Advice please on anchors

Post by deSouzaFrank »

I'd rather do this if you where only going to use it to attach yourself to an anchor.

[attachment=0]2FC8AD7B-7806-4F27-9C2F-80FBF4D659DD.jpeg
Attachments
Personal anchor system
Personal anchor system
SNORT
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Re: Advice please on anchors

Post by SNORT »

Personal anchor systems (PAS) are expensive, bulky and have limited use in the South African context. Useful in big wall bolted sport climbing or where anchors are fixed like in Chamonix rock routes and when abseiling in a party of three or more . Ordinary slings are much more useful.

Adjustable PAS's like the PETZL connect (https://www.petzl.com/US/EN/Sport/Lanya ... ECT-ADJUST) are useful when aiding and working big wall routes or trimming large branches on trees. But again are expensive and bulky and add to the clutter on one's harness.

In fact I used one for a while at Yellowwood and now it lies idle in my gear cupboard.
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Nic Le Maitre
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Re: Advice please on anchors

Post by Nic Le Maitre »

Simpi27 wrote: Fri Jan 21, 2022 11:05 am Howzit I'm looking for some advice on making your own slings/ anchors from rope. I've got an 10mm rope. So my question is do I tie a figure of 8 or a double fisherman's so that I have an anchor?
I'm a beginner so hope I'm making sense?
If you want a permanent loop, then the double fishermans is the way to go. For a loop that you are going to want to undo again after loading, a reef knot with a fishermans on either side works very well.

The flemish/figure 8 bend is what you want to use if you are really only familiar with the figure 8 knot. https://www.animatedknots.com/figure-8-bend-knot, pay careful attention to how it differs from a figure 8 on a bight etc, with the loaded strands coming out of OPPOSITE sides of the knot
Happy climbing
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deSouzaFrank
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Re: Advice please on anchors

Post by deSouzaFrank »

SNORT wrote: Mon Jan 24, 2022 6:44 am Personal anchor systems (PAS) are expensive, bulky and have limited use in the South African context.
One in picture is 6mm accessory cord and a maillon.
Petzl Maillon R80
6mm static R20/m
Total of R120. Not expensive in my opinion.
Have never found it to be bulky either. Coils nice and tight and hangs comfortably, out and of the way, on my harness.

I found it useful on multi-pitch sport routes. Even doubles as a shelf at belay stance. The fishermans knot attaching the two biners i replace with clove hitch and the system is adjustable. I found it useful lying in the kit bag until its time to clean a single pitch route. I found it useful for prusik back up on abseils. It has been years since I’ve ditched slings. For me this setup works better.
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raphaeltube
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Re: Advice please on anchors

Post by raphaeltube »

Hi Michael

#1 - This is the kind of thing best asked, explained & demonstrated in person. -it is safety critical.

Personally, when sport climbing (which I presume is what you'll be doing as a beginner), I prefer to use a cowstails as per Frank's pic.
Note, a personal anchor is only necessary for 'cleaning' (threading the rope such that it can be pulled down without leaving any gear behind), which as a beginner you should probably leave to someone with some experience.

Also, I'd go with the 10mm rope that you have, over 6mm static cord.
Static cord (or dyneema slings) are fine, as long as you are always hanging below the anchor that you're attaching to.
However, I often like to go up & sit on the ledge at the top of a climb (above the anchor) & enjoy the view when I finish a climb, which gives the potential for a factor 2 fall (I recommend reading up about fall factors), in which case static cord or slings are not appropriate.

The knots used to attach the 2 'tail' carabiners is a Poacher's knot (or with an extra wrap, a scaffold knot):
https://www.animatedknots.com/poachers-knot
*It is very important to test these (full weight, but on the ground) before putting your life on the line, because if done the wrong way 'round (hard to spot visually), it will just slip out.

For reference, here's the figure 8 on a bight:
http://www.ropelab.com.au/wp-content/up ... ressed.gif

-R
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Re: Advice please on anchors

Post by deSouzaFrank »

Sorry Raphaeltube.
But in my opinion you’re playing with fire. Dynamic or static if you fall twice the length of your tether your pulling factor 2 forces on the bolts and gear. NEVER be on ONLY the slings or PAS. You should stay tied into rope that is dynamic and running all the way back down so you’ll have no factor fall worries. Even whilst rethreading when cleaning i tie a fig8 on the bight below the fig8 that im tied into, and clip 8 on a bite to harness with locking biner, then only undo the main fig8 and rethread. Never, not even once do i hang off of a sling or PAS alone. ON BELAY ALWAYS.
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Nic Le Maitre
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Re: Advice please on anchors

Post by Nic Le Maitre »

The guy wanted advice on how to make rope loops...
I think you're getting slightly off topic
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deSouzaFrank
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Re: Advice please on anchors

Post by deSouzaFrank »

Nic Le Maitre wrote: Sun Jan 30, 2022 12:54 pm The guy wanted advice on how to make rope loops...
And you reckon 2 loops made out of 10mm rope is going to be just fine? Good luck at the anchors with those fat boys both larks foot/cow tailed to your belay loop. Yoh!!!! Not for me hey. Just imagine using that. Come on man. Not dangerous but a very kak idea.

Someone has told a beginner its okay to top out on your slings alone and then its off subject if i try and rectify this.

So, if i may Rope-Lab-Nic, im only giving my opinion here.
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justin
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Re: Advice please on anchors

Post by justin »

Whilst we're off topic... best don't be putting Larks foots onto your belay loop either - thread it rather through your waist and leg loop.
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Nic Le Maitre
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Re: Advice please on anchors

Post by Nic Le Maitre »

Simpi27 wrote: Fri Jan 21, 2022 11:05 am Howzit I'm looking for some advice on making your own slings/ anchors from rope. I've got an 10mm rope. So my question is do I tie a figure of 8 or a double fisherman's so that I have an anchor?
I'm a beginner so hope I'm making sense?
deSouzaFrank wrote: Tue Feb 01, 2022 4:27 pm
Nic Le Maitre wrote: Sun Jan 30, 2022 12:54 pm The guy wanted advice on how to make rope loops...
And you reckon 2 loops made out of 10mm rope is going to be just fine? Good luck at the anchors with those fat boys both larks foot/cow tailed to your belay loop. Yoh!!!! Not for me hey. Just imagine using that. Come on man. Not dangerous but a very kak idea.

Someone has told a beginner its okay to top out on your slings alone and then its off subject if i try and rectify this.

So, if i may Rope-Lab-Nic, im only giving my opinion here.
Dude, chill out a bit. If you read the actual question, he's asking how to use rope to make loops and which knots to use. He didn't say he wants to clean routes or sport climb. He might want to know how to set up a retreat off a route using tat.
Happy climbing
Nic
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Re: Advice please on anchors

Post by deSouzaFrank »

@Simpi27.
Please clarify this for us. What do you intend to use this for?
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raphaeltube
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Re: Advice please on anchors

Post by raphaeltube »

viewtopic.php?f=1&t=24064

Same poster, same day. I made some assumptions & chose to reply on the more active thread.

-R
Old Smelly
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Re: Advice please on anchors

Post by Old Smelly »

Justin

I have avoided a Lark's foot attachment for everything always - not using it on slings or anchor systems or ropework.

BUT now - the Dual Connect Adjust from Petzl - the Rolls Royce of Personal Anchor Systems - recommends attaching with the Larks foot to the Belay Loop.

Now I know Petzl mean this as a personal anchor system - not a Dynamic Tether for falling on or belaying directly off it - but using a Larks foot is adding a weakness to the system. Sure they use rope (not sure diameter but it is rope and dynamic). Now one can attach it with a circular link (Petzl make that too) but that is not as per their design.

So is that ok?

I see Snorts response is to basically avoid Personal Anchor systems, but in respect to the general sport climber- I often encounter people who have been taught by their mentors to use two permanently affixed 60cm slings larksfooted to their harnesses. My thinking is that any Personal Anchor System is better than this method. The need for a tether for a Sport Climber is real and systems like the Metolius PAS do that job admirably - even though they once again use a Larks Foot attachment. In terms of PAS systems it seems that generally they are set up to use Larks Foots.

I think that the initiator of the mail asked the right question - if he wants to use a rope tether then what knots should he use?

All current evidence considered a rope tether is a good option - knots aside - rope appears to retain more strength and shock absorption ability than slings. Sure the knots reduce the strength and thick rope is cumbersome but if you get those right you will certainly be in a better situation that someone on 2 60 cm slings. SO this solution could be optimal - you may even be able to use a thin piece of dynamic rope and be better off. The knots remains the real debate - I would use figure eight knots on the ends (possibly with fishermans) and a figure eight or Alpine Butterfly on the middle - which one could attach with a carabiner or Demi-rond Maillon (or a Larks Foot).

This would make it a good tether with some dynamic loading ability - with deference to the fact that one should wisely always keep the rope in the system as the shock absorbing element.

So is the rope style Lobster Claw/ Cows Tail system the best most cost effective tether method at this point- well.....possibly...

Sport Climbers need tethers. Everyone should keep the rope in the system - even when cleaning use the best possible practices to keep the rope in the system like passing the rope through the chains (Petzl system). Even when using a Quad use your tethers for cleaning.

Does anyone have a better Tether System? The Petzl Dual Connect Adjust seems to be the best currently available but carries a high price tag. Does anyone know of anything better?
Really, its not that bad...I think it's my shoes...
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Re: Advice please on anchors

Post by Marshall1 »

@ Justin, why not just use draws at the chains? Cow tails are clutter, that get tangled & they have single use. Draws are simple & multi-use.
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Re: Advice please on anchors

Post by grae22 »

Hey Old Smelly

I was under the impression thinking had changed and "real world" testing (e.g. HowNOT2) has shown most of the fear about the Lark's Foot is unjustified (sorry I don't have a reference on hand).

I'm not sure I follow why having a tether is particularly important for Sport climbers - other than multipitch routes where you may need to untie from time to time, I can't think of a use-case. I don't use a tether for cleaning, the prevalent modern methods where one stays on belay the entire time seem "super good enough" for my tastes (i.e. probably much the same as Marshall1 suggests).

What about a Purcell (http://www.bluugnome.com/cyn_how-to/gea ... ether.aspx)?
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Re: Advice please on anchors

Post by SNORT »

@ Justin, why not just use draws at the chains? Cow tails are clutter, that get tangled & they have single use. Draws are simple & multi-use.
My point exactly.

However some people just love gear and gadgets and stuff and are easily upsold into these devices.

Having been in the game for over 40 years I make it a point of trying out new gear that comes along and there certainly are amazing improvements that come along from time to time. The Edelrid Jul and Ohms are a game changers. Micro-tractions are very useful too. And I also have two PASystems that I am happy to sell. One is the Mammut Daisy Chain type and the other a double tailed Petz adjustable

Adjustable PAS's can be very useful if you are doing multipitch guiding with more than one person, rope rigging, working a route, bolting and cutting down trees. In short, it is useful for technical rope work where small easy and quick adjustments make a difference. This can save time and energy like when having to lean out and cut a branch of a tree with a chain saw or to drill a hole to the one side or high above one's anchor point.

But for the vast majority of climbers, quite frankly, it is just cost and clutter. But as I said some people really are just gear junkies like so many people that get involved with rescue. They love the dozen large screw gate biners, the massive triple racks, pulleys and stuff. All that gear makes you strong I guess...

For me the less, the lighter, the better.

But by all means buy up and rack up. The gear shops will love you for it.
Russell Warren
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Re: Advice please on anchors

Post by Russell Warren »

Old Smelly

Please excuse my ignorance, but please explain this statement

"I see Snorts response is to basically avoid Personal Anchor systems, but in respect to the general sport climber- I often encounter people who have been taught by their mentors to use two permanently affixed 60cm slings larksfooted to their harnesses. My thinking is that any Personal Anchor System is better than this method. "

What exactly is the problem with the 60cm affixed slings?
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Re: Advice please on anchors

Post by Old Smelly »

Hi - with regards the 2 60cm slings-

2 things (maybe some more after);

They are a fixed length. So the position of the climber to the anchor is hardly ever just right for 2 60cm slings. Even if 1 of them is correct the other then takes no load- essentially it is useless. A good PAS allows one to adjust the length of the sling to a good working position.

Secondly - and just as important - if you cannot get the length right then at least make them able to absorb some shock loads - in case you now move about and induce slack and then drop onto your dyneema skinny sling - there is a chance they can snap (see countless articles on the inability of Dyneema slings to take shock loads). Now if you couple that with the Larks foot attachment - where the forces all go onto one short section of the sling and you are definitely trying to snap that little Dyneema sling. That's why a rope type sling is better.

So essentially that is a sub optimal solution.

A PAS sling with multiple loops can be shortened to take the load at the right distance. If you use one of those and clove hitch your rope to the anchor then that's better than 20 60cm slings - both can carry the load and one is shock absorbing and the other is loaded the whole time.

Then - even if you use the anchors created in the method of Nic and his cow with 2 unequal length legs - this system allows you to create 2 points of attachment that are equally loaded and can hole you well (and even if one failed the other would hold you in place). To me that is safer and better practice.
Some may say you could use a quickdraw and clove hitch your rope but then a quickdraw is hardly ever the right length - so that would be uncomfortable. Or you could attach directly to your Quad and clove hitch your rope to the anchor - otherwise the Quad is only one point of attachment.

Then you have to do as mentioned previously - pull up rope - clove hitch and create a new figure 8 - attach to your harness and undo the original knot, feed through the anchors and tie back in. That's all good.

If you have a double legged PAS you can clip in with both, shorten the adjustable one until they are both holding, pull up the rope and clove hitch it, make an eight, clip it to you, undo the original knot, slip it through the anchors, tie in and then unclip and remove knots and then your belayer can take up and you can go on to the rope and remove the PAS. With practice this is very efficient and carries no risk and at all time you are properly connected.
Really, its not that bad...I think it's my shoes...
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Nic Le Maitre
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Re: Advice please on anchors

Post by Nic Le Maitre »

Way to go off topic...
justin wrote: Wed Feb 02, 2022 6:55 am Whilst we're off topic... best don't be putting Larks foots onto your belay loop either - thread it rather through your waist and leg loop.
Yup, that way you don't get the pinching on your belay loop, or the super tight bends in the PAS/whatever. Follow the manufacturers instructions
Old Smelly wrote: Fri Feb 04, 2022 9:33 am BUT now - the Dual Connect Adjust from Petzl - the Rolls Royce of Personal Anchor Systems - recommends attaching with the Larks foot to the Belay Loop.
No, no they don't, they advocate putting it like Justin said.

Image
Old Smelly wrote: Fri Feb 04, 2022 9:33 am All current evidence considered a rope tether is a good option - knots aside - rope appears to retain more strength and shock absorption ability than slings. Sure the knots reduce the strength and thick rope is cumbersome but if you get those right you will certainly be in a better situation that someone on 2 60 cm slings. SO this solution could be optimal - you may even be able to use a thin piece of dynamic rope and be better off. The knots remains the real debate - I would use figure eight knots on the ends (possibly with fishermans) and a figure eight or Alpine Butterfly on the middle - which one could attach with a carabiner or Demi-rond Maillon (or a Larks Foot).
Yes, knots weaken rope, that is accounted for in the design of cowstail systems and their intended usage of protection while moving around BELOW an anchor. Cowstails should never be used in a system where there is a chance of large dynamic loads, at least not if you want to survive in one piece.
The "most" shock absorbing knots are actually barrel or scaffold knots. BUT their ability to absorb shock is related to the rope moving through the knots, so the knots need to be regularly untied and retied. The use of dynamic or semi-static rope makes very little difference to the shock absorbing ability of the cowstail. To fasten to your harness, it is recommended that the central 8 be tied as you would tie in, rethreaded.
Marshall1 wrote: Fri Feb 04, 2022 10:27 am @ Justin, why not just use draws at the chains? Cow tails are clutter, that get tangled & they have single use. Draws are simple & multi-use.
I agree completely. Just use the draws and the rope that you have with you.
grae22 wrote: Fri Feb 04, 2022 10:30 am I was under the impression thinking had changed and "real world" testing (e.g. HowNOT2) has shown most of the fear about the Lark's Foot is unjustified (sorry I don't have a reference on hand).
Partially correct. For the normal loads we see, and with nylon slings, it's not a problem.
Old Smelly wrote: Fri Feb 04, 2022 2:28 pm in case you now move about and induce slack and then drop onto your dyneema skinny sling - there is a chance they can snap (see countless articles on the inability of Dyneema slings to take shock loads).
Dyneema does just fine with shockloads, that's why it is used for quickdraws and slings that protect falls. What it does not do well is survive dynamic events when it is knotted. The melting point is very low and the friction through the knots as the sling moves under load heats it up sufficiently that it fails at low loads.
Old Smelly wrote: Fri Feb 04, 2022 2:28 pm Then - even if you use the anchors created in the method of Nic and his cow with 2 unequal length legs
I didn't say that.
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Old Smelly
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Re: Advice please on anchors

Post by Old Smelly »

Hi Grae22,

I do not think there is a real case which has discredited the claim that girth hitching or Lark's foot knots can decrease the slings strength by as much as 50%. I did find this case study https://blog.weighmyrack.com/wp-content ... Report.pdf

I think that we all know that if a girth hitch has been set correctly it can carry loads nicely but typically all knots weaken slings and the Larks foot is certainly one that applies all the load on a small area, so NO I cannot say that a Larks foot is a strong attachment - particularly with regards to Dyneema slings. I will look for more info but I am sure that shows it is sub optimal.

As to the "normal" method you refer to I want to know how you do this without a tether. As I mentioned before - you can use a quickdraw - but its not practical and I DO HESITATE TO MENTION THIS.... but even on this forum we have a discussion around how someone died because they did not attach themselves to the anchors and somehow undid the wrong knots.

Now - before you all squeal and we get another lecture on minimalism - which I think is misplaced for most sport climbers - the facts remain that when cleaning...

WHEN CLEANING - is NOT the time for all these smart ass shortcuts - it isn't!!! Attach yourselves with 2 attachment points before untying the rope, tie the rope in again to yourself -so that you are always on belay -DON"T try and do that without a tether (preferably 2) and then untie your original tie in and thread the anchors. The big idea is that you can tie in whilst on the tethers and you won't slip or fall and then you can remove your other tie in and see that your new tie in and belayer are holding you before coming off the tethers.

I cannot see why you would want to try and clean without a decent attachment point, unless its to boost your ego by doing something unnecessarily risky?
Really, its not that bad...I think it's my shoes...
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Re: Advice please on anchors

Post by Old Smelly »

Far be it from me to dredge up the unequally bolted anchor points argument...lets let sleeping cows lie...

I think your contention that Dyneema can take shock loads is largely incorrect - in fall arrest systems there is always a load limiter of some sort and when climbing the draws don't take the shock loads - the rope does...

For that I can find UIAA reports if need be...
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Re: Advice please on anchors

Post by Old Smelly »

BTW that picture shows a Larks foot of sorts...
Really, its not that bad...I think it's my shoes...
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Re: Advice please on anchors

Post by deSouzaFrank »

:lol: :lol: :lol: :puker:
Simpi27, if you intend to use this just to anchor to a route in order to clean it just use the system i have shared. Cheap, multiple uses, simple and effective, adjustable if clove hitched, no knots onto harness, no threading and unthreading from harness. Forget about all this kak above, (all of it though, very worth investing the time to do some research on) you’ll still get into all that technical stuff as time goes by. Ask any of these boffins above if the system i shared is wrong. Im pretty convinced they wont be able to prove something wrong with it.

Ps. Using quickdraws to clean in MY opinion is silly. Some routes you’ll struggle your *%+# off to get your harness up high enough to clip. I have tried this method and it has had me hanging from draws and my legs dangling below the overhang on which the anchor is bolted, crotch driving into a chicken head. Lekker long, adjustable tether would have left me with far fewer crotch bruises.
Attachments
Fig 8 and/or the two fishermans can be replaced by clove to make it adjustable.
Fig 8 and/or the two fishermans can be replaced by clove to make it adjustable.
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Nic Le Maitre
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Re: Advice please on anchors

Post by Nic Le Maitre »

Old Smelly wrote: Fri Feb 04, 2022 4:36 pm I think your contention that Dyneema can take shock loads is largely incorrect - in fall arrest systems there is always a load limiter of some sort and when climbing the draws don't take the shock loads - the rope does...

For that I can find UIAA reports if need be...
You do know that the xx kN rating on your equipment is a measure of the force that the equipment can withstand? And that force = mass * acceleration? So a 12 kN rated sling/draw be it made of nylon, dyneema, Kevlar or cheese can withstand 12 kN force, irrespective of how quickly that force is applied, fast or slow?

I'd love to see a UIAA report that shows Newtonian physics is incorrect, please share.
Old Smelly wrote: Fri Feb 04, 2022 4:37 pm BTW that picture shows a Larks foot of sorts...
The larks foot is through the waist and leg loops, not around the belay loop, which is the important part.
Happy climbing
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Re: Advice please on anchors

Post by Marshall1 »

@ Old Smelly, unequal top anchors are kiff!
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Re: Advice please on anchors

Post by Old Smelly »

To Mr Marshall - Cool - Enjoy!!

With regards to Momentum (and Newtonian Physics):

Momentum is based on Mass and Velocity. Static Strength does not relate directly to Momentum. Lots of things can take a big load applied slowly but react differently when a smaller load is applied quickly. Climbers understand this - that's why a static rope can take a big load but not a shock load versus a climbing rope that can absorb a massive shock load but stretches a lot more - to absorb the shock load (30%).

So what about the strength rating? Well testing has shown that different slings made from different materials absorb shock loading differently - even if they are all rated at 24KN.

So basically the assertion that a force is the same whether applied quickly or slowly is an oversimplification at best and dangerous in that form of interpretation. An 100 Kilogram climber falling a metre can generate a lot of Momentum and will most likely still be accelerating when the sling takes the load - in no way similar to placing a 100 Kg load on a sling or rope.

I think this video is quite clear on the differences:

https://dmmwales.com/Knowledge/June-201 ... %AE-Slings

There is a whole calculation to momentum and forces involved that shows that Momentum Forces are what needs to be considered and not just the ultimate strength of the sling but I think that point was made in the DMM video.

I am not sure what point Nic was trying to make but there is definitely an advantage to using materials that absorb shock better at the same strength rating as compared to those that do not absorb shock well when it comes to a personal tether.
Really, its not that bad...I think it's my shoes...
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Re: Advice please on anchors

Post by deSouzaFrank »

:hapban This is so much better than the usual “garage sale posts” :hapban

Nic i believe it's your turn to reply.
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