What breaks first?
ฝัง
- เผยแพร่เมื่อ 16 ก.ย. 2024
- How much force does a climbing cam exert outward on a rock? Is it 2X the force pulling down? Is it 4X? Something completely different? It’s easy to calculate, they say. It’s just simple math, they say. Then why is there so much discourse about this “simple” matter without a clear answer??? We tested it!
CLIMBING CAM OUTWARD FORCE TEST RESULTS
👉 Short answer: it’s 2x the force outward as you pull on the cam. Detailed answer is in our graphs and spreadsheets. Find those on the downloads page you get when you sign up for emails. If you are already signed up, the "downloads page" is at the bottom of every email we've sent - hownot2.com/si...
WHY DOES IT MATTER
Accidents are unfortunately a part of every aspect of life, including climbing. And while your climbing gear is designed for and rated to hold a fall, the rock into which it is placed is not. This leads to instances like what happened in Taylors Falls, Minnesota, where an anchor built with three cams placed into a single vertical crack failed when it was weighted. - publications.a...
Sometimes your only option for protection is NOT as bomber as you'd like it to be. If that is the case then it’s beneficial to try and minimize how much force would be exerted on the rock in the event of a fall.
👉 Cam Angles, tech specs and our own engineer drawings are on the cams we sell at hownot2.com/co...
👉 Discuss these results on Discord Forum
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Let's see. 1. Included manufacturer's published information. 2. Got feedback from two different of interested nerds. 3. Included tests done by someone else. 4. Pulled on shit and recorded the results. 5. Changed the test fixtures from criticism and more reflection. Ryan, I'm impressed.
that "now stick with me stupid" really pulled my focus back lmao
I don't even climb...but I am a test engineer and this is how you do it. Way lots of arguing up front, then just pull on stuff.
Facts! haha, I worked in a structural research lab for years and loved the unknown and the "let's just break it" conversations
@@alextemus My doctor had this job, when working with implants with the human body, he broke so much expensive stuff that they tried to build a robot to get rid of his job.
High praise, that.
i dont know man i just boulder
😂 i cant boulder, i just like watching stuff break
For now….
I only climb straight, plumb, level, and at most, curved video walls. Double dorsals and a grillon are all I need for a fun day at work (full harness tho).
Still love this content.
@@CharlMarais247 same. I don't care that much about rock climbing. I just find the breaking of stuff neat 😊
Sublime 😂😂
This is one of the best videos you guys have ever done. This is actual science. Theory, prediction, test, results, analysis, repeat.
Now the real question is how much force rock can take.
All the kN if it's big enough. Just make sure you climb on a UIAA rated rock!
With enough freeze/thaw cycles going into a crack, it eventually goes to zero. As anyone who has seen a rock fall off a cliff can verify.
well i know from practical testing that a motor hood sized block of rock can be too small to hold a tiny whipper of about 10cm. It did look well connected to the rock, which it obviously wasnt because I ended up on the recieving end of that thing. fun times!
I usually go by if I can yard on the flake with directional force in it’s weakest direction it should be fine but just stitch that crack up and climb carefully and trust the choss
Yeh that was the real interesting question for me. I think we all know that cams hold if their well placed.
What I really wanted to know was how chossy looking a piece of choss needed to look before it wasn't worth shoving something behind it.
Evidently there's relatively infinite variables, but still, that's the significantly more useful question to placing pro and building anchors.
I've learned more watching your channel than I did in 40 years of sketchy trad. Thank you for making climbing safer, and both elevating and deepening the conversation.
Getting 100-200 people all focused on the same problem can give you amazing results. I hope we start seeing this more and more on big science questions.
Great job everyone.
“..even though the cam gets smaller the more scared I am…”. had me laughing out loud. I definitely relate to that statement 😂
Serious balls for trying to tackle this
Unexpected cross over to down under! Love the colab :)
I love your chanel, you used testing to prove physics is right, it's fun to watch. As an engineer, I would like to let you know that why the cam forces is one of the easiest to calculate in climbing gear. The model can be simplified to your drawing, and that simplification is close to real life. In contrast, any gear's MBS is a much harder problem to solve on paper, so hard in fact the design and verification heavily rely on real world testing. It's because when material properties and complex material shapes come into play, the math becomes super complex, and there are too many variables that we do not know or fully understand. For example, the MBS of a carabiner would be too complex to hand calculate, even software calculation is not very reliable. That's why we love seeing break tests, they are the valuable information we can't find else where, and the big brands don't like to share them with us.
Nice work mate! Covered it pretty definitively. And saved me from ruining any more cams 😂
Ryan's acting chops are unironically getting really good!
You know the math is getting serious when the TI-84 camme out
Color version too!
Do you get your load cells calibrated occasionally? I work in a testing laboratory and use load cells all the time and they can drift drastically over time especially with shock load. Like I'm talking 12%
I work in live entertainment and have always begged for motor point load cells, especially on some super tight and maxed out rigs. I’ve seen Kinesys automated hoists several times and have yet to see a dedicated “static” load cell ever deployed on a rig.
Wohowowho what stuff are you using? I've never seen a load cell drift more than 5% from it's original calibration certificate and that's after serious overloading
@@REVOLUTIONS51 We use load cells for geologic applications and they definitely drift quite a bit, particularly when left monitoring stuff for years. I think it just depends on your application. We've definitely seen sensors drift over 10%. Leads to lots of data management fixing sensor drift
Given his joke about how the ink on his protractor hadn’t been calibrated that week, I suspect he’s aware of the importance of calibration.
been waiting since forever for this video - thank you so freaking MUCH!!!
I love how the Simple answer doesn’t change me wanting to see you try and break/test things. Math lie but variables and human error is wild
I'm stopping at 06:15 to comment and validate (again) that I've been climbing since the 60s, I was an AMGA guide, but I also have a background professionally in traditional vernacular stone quarrying, carving and architectural restoration...PLUS...lol...a solid background in geology...!!! And that placement is a "DEATH TRAP" for so many reasons I can't list them all...LMAO...!!!...LOVE THIS CHANNEL!!!...and perhaps the best I have seen on climbing and rigging from the perspective of what people need to THINK ABOUT!!! when in the vertical world...I will edit as I watch...
That was awesome. I feel the need to clarify, though that aluminum is a pretty isotropic material. I wouldn't describe it as anisotropic, but maybe you could test that assumption, too.
Great stuff, thanks! Always was taught cams outward pushing force is about 2.5 x the force put on the stem, so this was great to see!
huh, my gut definitely said at least 4x the force. always great to see real data. now I'm wondering, how much outward force does passive protection exert? nuts are just small wedges, after all.
I'm interested in this as well. While I don't generally want to risk placing behind sketchy flakes, if that's all that is available knowing those numbers could help with the choice of placement. The Tricam data is super interesting in this way.
Sweet jig for testing dude. You gotta have the best climbing gear channel out there.
One of the best videos I've seen on TH-cam. Science and breaking stuff.
Would be interesting to see the known Omega Pacific cams! Thank you for the correct interesting approach as always.
Looks like a lot of effort went in to this video. Well done, very interesting! 👏🏻
"Peer reviewed on youtube and discord" 😂😮😂
dude, you are awesome,
the only thing i would make sure to have on the final rig is some kind of structure to make sure the surfaces contacting the cam and the load cells stay in place, a fun solution to angled contact might be to use a big ball bearings as a spacers to make sure the load cell is not getting angled contact with a flat surface, another idea is that it might be easier to put the spacers of the outside of the load cell where uneven contact might not be a problem, maybe a big thread or something like that might make the work as a spacer and now the only problem to solve would be how to make sure the contact plates don't angle with the cam.
I love that the new rig also offers the possiblity of doing the friction tests on it cuz everything is swapable.
On the process side of things, it might be interesting to take pictures of the cam under load so that you can measure angles and points of contact from the picture, potentially giving you the option of calculating friction coefficients in the future.
A little practical physics just before 9:00 really kick starts my day. Thanks.
The friction involvment is twofold. Of course, as it was said multiple times, coefficient of friction against the rock doesn't matter as long as it isn't slipping, but there's also coefficient of friction within the pivot which acts as additional torque on the arms of triangle in the diagram. which should lower the outwards force.
This is exactly the kind of scientific breakdown I love to see! The combination of theory, testing, and analysis is super informative.
Have you considered creating shorter clips highlighting specific topics like this one? Bite-sized content as TH-cam shorts could be a great way to reach a wider audience of beginner climbers interested in the science behind safe climbing practices.
I offer a service that can help automate this process of repurposing your content into shorter videos, so you can focus on creating more awesome in-depth videos like this one.
nerd skit is gold. 👍🏼
I didn't realize until just now that your channel has been missing project build montages!
Compass ink was low so it threw off the number. Please refill the ink and try again. Showing your answers in long form. GREAT VIDEO. LAUGHED OUT LOUD.
The views you slipped in at 5:50 are freaking heavenly and could convince about anybody to be a climber
Amazing to see a big flake- block shift position on the cliff, after placing a small to medium cam & testing the placement.
Amazing work as usual to everyone involved! Ill make sure to get my rock cerified before i whip 😅
Looks like I'll need even more tricams.. great video :D
People being nice and being able to change their mind is facilitated by contact with objective reality. Math and experiment do a lot to force egos to heel. Its not a perfect system, but it is much better than the alternatives.
btw I don't climb (yet) but I find the testing on gear that can be used in other use cases (even for tying stuff, like ropes, knots and so on) is pretty neat. One can also use carabiners to tie things so this channel is great already for the testing. Further even if it testing stuff I will likely never use, if the test is well done, it shows others how to do a proper test AND how to build test equipment.
Since the cam is pulling those friction plates into the side of the frame there will be an inward friction force opposing the cam's outward pressure meaning the measured outward force will be lower than it actually is.
Not by much, as the outward component of the cam's action is not in line with the friction component you're mentioning. The results is a pivoting action where most of (like in the order of 99%) the original sideward force is transmitted to the load cell.
1:21 engineering explained… please tune this 5s into a 20min vid. That sounded super interesting. Cheers and thank you
It would be interesting to measure the tricam with different camming angles (from a tight fit to some less bomber placement you would be afraid that it can walk out). I expect forces ranging from what you measured (for a tight fit) until forces similar to a friend's in a wider crack.
I would be very interested in tests with ballnuts. I'm not sure about my math, but I get a factor
Dang, going to reevaluate my flake placements after this one!
The definition of statistical testing is doing the same thing again knowing that each result is only one sample out of a population of possible results and you need to repeat the test to develop an understanding of the overall population
The width and position of the cam in the force jig is really important for measuring the force. Since it's really small, and you never get it in exactly the same position, you'll never get that right.
Edit: ahh commented before watching the entire video. Good thing you changed the rig!
well, enthusiastically hit Like at "now stick with me stupid" lol
You should have been a writer on Star Trek with that brilliant techno babble 😂
This one is Awesome! Love the new wooden jig and paint stick XD
0:47 that was actually impressive
Very sophisticated setup 😮👍
So much information in detail what a fantastic video thank you very much
really good video!
genuinely is helpful for assessing placements!
Absolutely fantastic video, it is great to see some real world measurement.
“It’s simple 🤓” then bro cooked
Sorry about my comment on the other video. Could have been a bit nicer. I'll admit that I was pretty relieved to see the numbers back up the math!
Not sure how feasible it would be, but i think a dynamic test on a drop tower would be super interesting. Does an expanding flake "cushion" the fall and lower the peak force a significant amount? If the cam starts skittering out / breaking crystals, what happens?
Cheers
You're missing the pocket protector to go with your safety glasses.
Brilliant !!! Just Brilliant !
- the "lever machine" - will have some strange binding / frictional issues pulling on a cam as it is operating in 2 planes with out of plane torque on the levers..
The compression cell tester looks good - maybe place the pads on low profile drawer sliders to remove friction (even if insignificant)..
Large C4's, Totems & Dragon Flies
amazing video ! thank you !
Hell yeah construction montage
Please do the headlamp video!
And now ya gotta do the math on how much force that translates into breaking the fulcrum of those long rock flakes depending on how far you place the cams from where they connect back to the rock?
Can we just emphasize that even if a cam has a slightly different angle that transfers 10% less force outward, your anchor is almost certainly either adequate or not adequate.
In other words, even if we learn how to lower the lateral force minimally, the discussion ought to be thrown out in favor of "how do we actually make this a bomber anchor and not leave things to chance with a tiny change in safety margins.
I love the channel, I just want the emphasis that this isn't something that should make a climber feel artificially safe.
When it comes to climbing channels, there can be only one! 🏆
This episode just decapitated all others!
0:45 really reminded of of Engineering Explained there.
That's a great one Ryan
Awesome video! Just awesome 😊
Thanks!
but its 2x on each lobe, so wouldn't it be 4x overall force? 14:30 you have 1kn pushing on the vector to the left, and 1kn pushing on the vector to the right. that means the fixture (or the crack) is seeing a splitting force of 2kn right? or 4x the tension. I think your original jig would give a better indication as to the splitting force on the flake
By the same reasoning, a bathroom scale you're standing on would be showing 2x your weight - being squeezed by you from one side and the ground from the other.
But your logic would be correct for mechanical work (force * distance).
It's definitely most accurate to say that the force from the cam on the rock is twice the downward pull on the cam. It's true that a single rope holding two opposing plates would have tension equal to 4x the downward pull on the cam, but that isn't really representative of what's going on when we place a cam in a crack, or how a flake would fail. To figure that out, you'd need to know the specifics of the placement, the flake geometry, and you'd still use the 2x pull force in the 3 body diagram. I hope this makes some sense, I desperately wish I could draw a diagram 😅
@@serges5681 no it wouldn't, there's only one vector force in that analogy - my weight. here there are two - from two lobes pushing in different directions.
@@jtambo13 see what your saying, and agree its 2x the force on the rock, but the rock on either side of the flake must meet at one point. if you subtract the vectors on each side of the rock 2t - (-2t) you have a force of 4t on where that flake converges (the point that will fail) right? i think the point isn't how hard the cam pushes on the rock - its how much splitting force the crack "see's" which will be the failure mode. my brain hurts
@@jaskiranism there are two force vectors, a vector from the person's weight, and another from the ground in the form of a normal force. Any time an object isn't moving, the forces and moments of the object need to be balanced
Love this video
Great video
Yes, your cam can break rock if it's a flake or fin. I've especially found this to be true on sandstone such as Red Rock NV.
Good Job! Friction still not a factor, because it is too dependent on too many factors you really don't want to guess at.
Yeah it's easy enough to remove friction from the equation and just calculate the normal force, but for the testing friction was still really important. My little rig with the wooden spacers went through several iterations to find stuff that's easy to adjust but wouldn't slip
Great video, but did I fall asleep and miss all the flakes/rock exploding???
Hey Ryan, do you want a welded frame made for your jig? I'm based in Portland and can definitely make you something that looks pretty nice out of steel angle and plate
This man is an engineering genius and yet he is using Philips head screws (12:42)
i can't help think that anything with a malleable material like wood in the system will distort the results?
I originally thought the same. But, I think if the wood gives a little you would see a reduction in both outward and applied force and the ratio would be the same
Anchor from a single crack always made me nervous
So this setup should also be able to test nuts by adding angled distance pieces. Wondering how much those will be
When are we going to test whether or now our spines are supergoodenough and for what kN?
Someone needs to make you a lexan 3/4" thick shield for the line scale.
When it comes to rock - I would imagine dynamic and static force responses will be quite different. Even with a cam engaged to a large flake - a ton of mass is going to have a damping effect in a dynamic loading case.
shouldn't the ratio of pulled distance on the cam to the amount it spreads be the easiest way to "calculate" the ratio of outwards to pulling force?
so if you pull 4cm and the cam spreads 2cm you have a ratio of 2/1 so two times the spreading force?
Sadly I can't find the pulling distance on your technical drawings. Would be awesome if you could "test" my theory.
I'm no expert when it comes to load cells so pleas tell me if I'm wrong but I'm a bit concerned about how much side loading they experience in that setup. Does that not affect the measurements?
Where does the turbo encanbulator fit on that cam?
i mostly use knotted slings in cracks..
2.0 tester is so much better
Did you get that protractor from the dollar store??? Im not saying it is wrong but the angle on the bottom of that thing is WILD
The friction does matter even if the object is not moving. There is a static friction coefficient for every material that is actually larger than the dynamic for the same material. If you could imagine a perfectly smooth, frictionless surface, the forces wouldn’t better because there wouldn’t be any resistance if you were pulling the cam out Parallel to the surface ti was wedged in. The friction force is calculated by the coefficient of friction time the normal force (force that the cam is pushing into the rock) this friction force is what’s keeping you on the wall. There is no velocity component to the equation. Not that any of this matters though if you can actually test it😂
Ah just got to the part of the video where you said friction is a factor 😂😂
Yeah, but if you don't overwhelm the coefficient of static friction, everything is...static. The forces measured will be the same as if the objects were welded together. So, unless it's actually slipping, you don't need to account for friction to measure what he is measuring.
Rigorous!
It is math! Love it
Wow super cool
So would the block hold?
So, use the smallest cam that works and or use it undercammed so that the available range of motion is the least since we have no idea if the rock is going to break, so make it move the least? OOOOR if you do that the rock moves and your cam pops out? arrrrgggg choices of death.
Afraid to assume Ryan is not a trained engineer, however what I'm getting at is Ryan is a better engineer than most trained ones. You don't need a degree to be an engineer, you need a certain way of thinking and analyzing at a detail level while being unbiased.
You definitely need a degree. Degree means you understand all the fundamentals. Thatyou understand where ideas come from. How to do certain things. This is for sure engineering but he is definitely not an engineer
He’s doing engineering by using an entire discord server of engineers to solve his question. He’s not an engineer
@@sempi8159 You're framing this as if you're HR with job requirements. I've been an engineer for 20 years, based on this experience I say you don't need a degree to be an engineer, you need a specific mindset and way of thinking.
I didn't go to school for electronics or programming, yet I have thousands of hours doing it, I don't need some scam school diploma to prove myself. I just bring a portfolio or projects I have accomplished. For example when getting into my current job, I had designed from scratch a BMS, including PCB layout and assembly. I was on my 3rd design going from all through hole to now majority dual side surface mount, all hand assembled by me. I am now in lithium battery development as an engineer.
I bought a econobox turbo car, learned to tune engines with it with many hundreds of hours and 500 flashes, that got me into OEM engine development assigned to a dynamometer and technicians to run testing for several years.
I went to school to become an auto mechanic.
This is mostly still science, where you try to figure out how something works, rather than engineering, where you design something to work a certain way.
That said, yes he's very good at this. And I'm a scientist irl.
@@MountainMullet Engineers have to be Scientists, Scientists don't have to be Engineers. Physicists don't make hadron colliders, Engineers make them, helping bring things back to reality so it actually works.
I think my original formula (although I typed half asleep, and forgot the "* 2") still seams to yield better and closer results to yours at video 15:00min mark.
Formula: Force * cos(angle) * 2
I use this formula a lot on in my work. Note if you do this in excel its: FORCE * COS(RADIANS(D4)) * 2
I look forward to seeing more, I am very curious about the pivot points on the cams, I will have to buy one and explore more.
I’m sorry… can you repeat that???
So... did the rock break?