Route Guide    Partners    Forum    Photos    What's New    Journal        
Sign Up  |   Log In:Login with Facebook
REI Community
The deadly ATC
View Latest Posts in This Forum or All Forums
Page 10 of 14.  <<First   <Prev   8  9  10  11  12   Next>   Last>>
Follow replies to this topic? Notify me at the top of web site.
1

Email me.
 
Jan 11, 2017
anotherclimber wrote:
Mammut does not make that easy to find those manuals. What's so difficult for them to link the manuals right on the product page like most every other manufacturer does?


The trick is to remember most manuals are pdfs. So you can tell Google to only show pdf results. I just Googled

Alpine Smart Belay filetype:pdf

I do this a lot to find rope catalogs. For example:

beal ropes filetype:pdf
dino74
Joined Sep 16, 2016
44 points
Jan 11, 2017
So jim. the kids actualy pushing it and catching lots of falls, climbing circles arround most of the folks on this discussion are not going to be able to catch a fall on a serious climb yet some wanker who has been at it for 20 years and only caught 5 leader falls will? these are all blanket statements and hypothetical specualtions. However> I do know a bunch of younger climbers who get out a lot, learned their stuff at Rumny, have caught more real falls that most of us old farts can even count. these kids that you don't have any faith in end up crushing cannon and then going on to bigger and better things like trying to free the Salathe etc, etc. On the other end of the spectrum there are pleanty of old farts that are complacent and have not caught a leader fall in forever. GET OFF MY LAWN...... Nick Goldsmith
From Pomfret VT
Joined Aug 23, 2009
15 points
6 days ago
Nick Goldsmith wrote:
So jim. the kids actualy pushing it and catching lots of falls, climbing circles arround most of the folks on this discussion are not going to be able to catch a fall on a serious climb yet some wanker who has been at it for 20 years and only caught 5 leader falls will? these are all blanket statements and hypothetical specualtions. However> I do know a bunch of younger climbers who get out a lot, learned their stuff at Rumny, have caught more real falls that most of us old farts can even count. these kids that you don't have any faith in end up crushing cannon and then going on to bigger and better things like trying to free the Salathe etc, etc. On the other end of the spectrum there are pleanty of old farts that are complacent and have not caught a leader fall in forever. GET OFF MY LAWN......


You made the speculative, blanket statement, not me:-
"there is no substitute for experience. either you have caught a bunch of falls or you haven't. The 5.6 trad climber who has been at for 30 years has less experience catching falls than a 2 year sport climber. When you launch into something serious it's nice to have the real deal holding your rope... "
Jim Titt
From Germany
Joined Nov 10, 2009
0 points
6 days ago
Nick Goldsmith wrote:
...learned their stuff at Rumney...


Now that is funny.

Nick Goldsmith wrote:
...have caught more real falls that most of us old farts can even count...


The daring and complexity of belaying short sport routes from the ground - oh my. Got it.

Can kids come up this way climbing hard? Sure. Can some then go on and 'crush it' at Canon and other trad venues? Sure. But make no mistake, it doesn't matter how hard you climb or how many bolts you've clipped when it comes to dicey trad lines where the anchors, pro and even the belaying starts getting seriously technical - you either have developed the hard-earned experience or you haven't. So yeah, there are the few exceptional ones and then there are the hordes of folks who can clip and tug 12's / 13's all day but who are barely competent to navigate the perils of real world multipitch, trad 9's / 10's let alone something actually serious.

Every year I see folks trying to cross-over from sport to trad and the vast majority of the time it just doesn't get much more sketch or scary to watch. I've had to intervene more times than I can count. For every Adam Ondra, Daniel Woods and David Graham there are several hundred thousand folks who attempt the transition somewhat at their peril in absence of the old mentoring approach JimT mentioned.
Healyje
From PDX
Joined Jan 31, 2006
100 points
6 days ago
anotherclimber wrote:
So for the manual brake assisted belay devices it's more of a technique and education issue than a complete inability to catch a factor two fall by pulling upwards on the brake strand? I would think this would be important information for the manufacturer to make available to the user in the manual. There is a big difference between, "This device cannot catch a factor two fall." and "This device cannot catch a factor two fall unless you hold upwards on the brake strand." Which leads me to my next question, why hasn't any of these climbing gear companies made a dual slot belay device that passes the standard for assisted locking devices? I'm with you with the lack of information and testing from the companies making these devices. It's quite scary when you think about it. If gloves don't help with gripping strength, and if your using a brake assisted belay device that is not a Grigri... Does it not make sense for catching high factor falls? Your testing seems to imply that past a certain kN load everything but the Grigri would slip some rope through and potentially injure the belayer or make them let go of the rope which would could have them lose control of it. This would likely be catastrophic with the belay device inverted and both rope ends coming out of the top I'm guessing it would not lock. rgold, Thank you for the further clarification. How do you know the Alpine Up might damage the sheath?


The generally accepted view from those researching belay plates is you need to exert a braking force of around 2.5kN to reasonably stop a large fall including FF2 ones. This wouldn´t be sufficient for a major fall however, the Italian Alpine Club was of the opinion that no device (of the conventional ones) was capable of doing this without extreme rope slip and severe rope burns. This was after a number of tests using a live belayer and measuring the forces and slip. If you look at the results from Professor Stronge posted earlier or these ones from myself you will see that the tested "assisted" devices fail to achieve braking forces any where near this.

Rock Climbing Photo: Braking Force 9mm
Braking Force 9mm


In fact Bill Stronge´s results with a new treated rope indicate that they would barely slow my fall as I´m a fairly large guy. Wearing gloves reduces the danger of rope burns but also the hand force by around 20% which increases the uncontrolled fall distance still further, the Italians were getting stuff like 15m rope slip using more powerful devices and thicker ropes.
The further the fall the greater risk of the leader hitting something and the belayer becoming injured and losing all control.

As you can see from my graph the braking effect of the Smart and Mega Jul after the belayer loses control (hand force=0) is not sufficient to slow down a falling climber of normal weight, they continue to accelerate.

The hand force we can apply is another problem, from a number of tests done various researches use differing values depending on whether they take a mean value based on population or a simple average. The DAV and other used 25kg force as an average and the Italians (CAI) used 17.5kg force which covered 90% of their group, both of which mean there are a considerable number of climbers who cannot achieve a reasonable braking force.

The modern trend to thinner, dry treated ropes isn´t helping. Most of the research was done when ropes were thicker and belay plates generally more powerful. It´s also worth noting that Werner Munter (after whom the Munter Hitch is incorrectly named) was badly injured performing a belay demonstration, Pit Schubert who lead safety reasearch for the DAV was partially disabled after a belay test and the Italians abandoned their testing on safety grounds.

A number of companies have made auto-locking devices (for want of a better description) for two ropes. Hewbolt, TRE Sirius to mention two. Both dissapeared from the market. The Sirius would probably have passed the test and was a good belay device but suffered rather from excessive wear, with some further development it could be excellent but the patent is currently blocked by Edelrid. The Hewbolt I´ve no idea.

The Climbing Technology devices ClickUp and AlpineUp are different to the Samrt etc in that the rope is locked into a cunningly formed groove/step by the karabiner and achieves vastly higher braking forces easily capable of stopping a FF2 once it is in the locked position. However at high forces the point loading on the sheath has lead to problems particularly with older ropes, whether this would ever be experienced in practice is unlikely, personally it is a risk I would accept since ruining the rope is far preferable to dying. None of the other "assisted braking" devices have ever produced enough braking force to begin to damage the rope.
The Climbing Technology devices are the only ones I would consider using but I don´t.
Jim Titt
From Germany
Joined Nov 10, 2009
0 points
6 days ago
Definatly the get off my lawn mentality there. Could not see the talent and potentual if it was sitting on the ends of their noses.... Do a lot of stupid unsafe things happen at Rumny? hell yes. Do a lot of stupid and unsafe things happen at the Gunks? hell yes. Who would I rather have holding my rope. The kid who climbs 5.13 at rumny and has caught hundreds of real falls or someone who has never led anything harder than Dennis...... Nick Goldsmith
From Pomfret VT
Joined Aug 23, 2009
15 points
6 days ago
Again , all your talk means nothing unless you actually practice catching the kinds of falls that you are discussing. Nick Goldsmith
From Pomfret VT
Joined Aug 23, 2009
15 points
6 days ago
Jim Titt wrote:
...since ruining the rope is far preferable to dying.


FF2 falls suck as either the leader or belayer and being alive afterwards and then getting either up and finishing or down and bailing is the primary concern - screw the rope - you aren't going to care about the frigging rope after one of those falls other than can you continue on or bail with it and a bit of torn sheath wouldn't ruin my day either way under those circumstances. If you're concerned about the sheath get a unicore and call it good, but almost no one here is ever going to experience an FF2 fall or anything near like one.

Knowing about such falls and how to avoid them is great; spending much time worrying about it is another case of poor risk prioritization - the number one risk being getting dropped. Avoiding that is worth spending time constantly worrying about every time you tie into a rope.

Nick Goldsmith wrote:
Again , all your talk means nothing unless you actually practice catching the kinds of falls that you are discussing.


Huh? Nonsense. Spending time becoming a competent belayer and being a competent belayer every single time you belay is worth expending time on and will serve you well if you ever have the misfortune of experiencing an FF2 fall. But contrived fall practicing? More or less meaningless towards actually holding such a fall in the real world as far as I'm concerned.
Healyje
From PDX
Joined Jan 31, 2006
100 points
6 days ago
The biggest thing is just don't put yourself in the situations where a FF2 is possible or probable.
I had a situation this summer where the leader was off route and got a bit frazzeled. The gear sucked and the climbing was way harder than what we were supposed to be on. The leader made belay right at a crux move that the leader did not want to try. I get to the belay and see that the gear is not great and the crux above the belay is protected with bad micro gear. This is the perfect storm to kill the whole party. If I was to aid on the crap gear and it failed I would FF2 on a belay with marginal gear likly flossing us both off the cliff. The same danger was there If I tried to free the move and fell on the bad micro gear. Both our lifes were dependant on one crappy flared out micro cam. If that failed then everything would be on a nest of crap I did not trust to hold a hard fall. I took a look at the situation and made a decision. I down climbed a few body lengths to a good stance with decent gear and made a new belay. I then instructed the leader that they had to either suck it up and finish the pitch or down climb to me and we would do a switch over and I would give it a try. Either way we had a new decent belay plus the previous poor belay as lead gear to protect the hard akward moves ahead. The leader chose to continue. It was a hard commiting move and I felt I did the only sane thing by constructing a whole new belay at a better location with better gear. The move cost us time but it helped keep us alive.
Experience and the confidence to 2nd guess the leader played a role in the decision makeing process.
Nick Goldsmith
From Pomfret VT
Joined Aug 23, 2009
15 points
6 days ago
Healy. these discussions are good in that they make you think about what can go wrong. My decision to construct a new belay in the story above did Not come from haveing caught FF2 falls , it came from reading about how bad they are. I do contest however that when really bad things happen like real hard falls the only thing that helps you react properly is muscle memory of haveing practiced something correctly... So I suppose if every time your leader starts a pitch without overhead protection you go over in your mind, pull up if they fall. that would certainly help. Belaying at the top directly off your harness and catching top rope falls with a downward pull also helps. The biggest thing is to drill into the mind. NEVER LET GO. Nick Goldsmith
From Pomfret VT
Joined Aug 23, 2009
15 points
6 days ago
Nick Goldsmith wrote:
Healy. these discussions are good in that they make you think about what can go wrong. My decision to construct a new belay in the story above did Not come from having caught FF2 falls , it came from reading about how bad they are.


And from having the awareness to recognize that's what you were getting into and having sound enough judgment to move the belay. Both are a product of experience.

Nick Goldsmith wrote:
NEVER LET GO.


At one time that was simple and adequate advice. These days I would add:

PAY ATTENTION AND NEVER LET GO.
Healyje
From PDX
Joined Jan 31, 2006
100 points
6 days ago
Nick Goldsmith wrote:
The biggest thing is just don't put yourself in the situations where a FF2 is possible or probable. I had a situation this summer where the leader was off route and got a bit frazzeled. The gear sucked and the climbing was way harder than what we were supposed to be on. The leader made belay right at a crux move that the leader did not want to try. I get to the belay and see that the gear is not great and the crux above the belay is protected with bad micro gear. This is the perfect storm to kill the whole party. If I was to aid on the crap gear and it failed I would FF2 on a belay with marginal gear likly flossing us both off the cliff. The same danger was there If I tried to free the move and fell on the bad micro gear. Both our lifes were dependant on one crappy flared out micro cam. If that failed then everything would be on a nest of crap I did not trust to hold a hard fall. I took a look at the situation and made a decision. I down climbed a few body lengths to a good stance with decent gear and made a new belay. I then instructed the leader that they had to either suck it up and finish the pitch or down climb to me and we would do a switch over and I would give it a try. Either way we had a new decent belay plus the previous poor belay as lead gear to protect the hard akward moves ahead. The leader chose to continue. It was a hard commiting move and I felt I did the only sane thing by constructing a whole new belay at a better location with better gear. The move cost us time but it helped keep us alive. Experience and the confidence to 2nd guess the leader played a role in the decision makeing process.


Tiny Epiphany: if you stop to belay due to a hard move, by definition the chances of a fall immediately off the belay are higher than normal.

(of course it seems tautological as soon as it is written down...)

Thanks, Nick. I am a little less likely to make such a mistake now.
mbk
Joined Jul 3, 2013
0 points
6 days ago
T Roper
From DC,VA,NM,UT,CT,MA
Joined Mar 31, 2006
730 points
6 days ago
dino74,

That is excellent! Thank you for passing on your trick to finding those things.

Jim Titt,

You are a wealth of information good sir! I'm very appreciative of you contributing here and you've answered a lot of my questions. To continue the conversation...

We can agree that with no hands on the brake strand in a loss of control scenario in a high fall factor, the Megajul and Smart Belay are not going to hold. Then again, neither are the ATC XP, BRD, and Reverso 3, so there is no advantage there for any of the devices.

But what about when there is full brake hand control of the brake strand? Even with gloves on losing 20% of grip strength, if the assumption is that 22kg of brake hand force is near the high end of what people can realistically do, you're still at 17.6kg which seems to be acceptable according to the information you provided with the Italian CAI (assuming I interpreted what you were trying to get across correctly). Especially since the Megajul and Smart Belay's curve flattens out at the top end there is not a large difference in belay force between 22 and 17.6 hand force. Oddly enough, this puts the Megajul, Smart Belay and Reverso 3 at about the intersection of each other in belay force. Is this still not enough belay force for catching factor two falls without unacceptable amounts of rope slip?

Which begs me to ask the question, what it the minimal acceptable amount of belay force provided from the belay device needed with full brake strand control to catch a fall factor two with an acceptable amount of rope slip? And wouldn't some rope slip be ok to reduce the violence of the impact of the catch on the rope, gear, anchor, and climber?

It also just occurred to me... Does the belay force of any given belay device double, or at least increase significantly when using twin or half ropes compared to single ropes in a factor two fall since both strands will be catching the climber? This would seem to be a simple solution to the problem if it were so.

Thanks again. I'm grateful for the time and effort you put into contributing here.
anotherclimber
Joined Apr 4, 2016
57 points
6 days ago
mbk wrote:
Tiny Epiphany: if you stop to belay due to a hard move, by definition the chances of a fall immediately off the belay are higher than normal. (of course it seems tautological as soon as it is written down...) Thanks, Nick. I am a little less likely to make such a mistake now.


This is brilliant! Thank you for posting this here. It's almost that same mental fear of wanting to clip over your head in sport lead, or place blindly over your head in trad. It may feel good to do so that way, but in reality the consequences can be much higher.
anotherclimber
Joined Apr 4, 2016
57 points
6 days ago
anotherclimber wrote:
... Is this still not enough belay force for catching factor two falls without unacceptable amounts of rope slip? Which begs me to ask the question, what it the minimal acceptable amount of belay force provided from the belay device needed with full brake strand control to catch a fall factor two with an acceptable amount of rope slip? ... I'm grateful for the time and effort you put into contributing here.


Let's save Jim a little time here. At the very beginning of his last reply is this little gem:

Jim Titt wrote:
The generally accepted view from those researching belay plates is you need to exert a braking force of around 2.5kN to reasonably stop a large fall including FF2 ones...


That braking force is actually just off of the Y scale on Jim's graph and it looks like, of the devices tested, the ATC XP is the only one that has a remote chance of achieving that, provided the belayer can exert a force of about 24 kg (also off the X scale and, therefore, extrapolated)
jktinst
Joined Apr 18, 2012
0 points
6 days ago
jktinst wrote:
Let's save Jim a little time here. At the very beginning of his last reply is this little gem: That braking force is actually just off of the Y scale on Jim's graph and it looks like, of the devices tested, the ATC XP is the only one that has a remote chance of achieving that, provided the belayer can exert a force of about 24 kg (also off the X scale and, therefore, extrapolated)


Thank you. That must have slipped by me on subsequent reads of his post trying to absorb and understand it. That's rather a scary thought that with the exception of the Grigri, the ATC XP is the only one remotely capable of catching this sort of fall.
anotherclimber
Joined Apr 4, 2016
57 points
6 days ago
Jim Titt wrote:
... The Climbing Technology devices ClickUp and AlpineUp are different to the Samrt etc in that the rope is locked into a cunningly formed groove/step by the karabiner and achieves vastly higher braking forces easily capable of stopping a FF2 once it is in the locked position. However at high forces the point loading on the sheath has lead to problems particularly with older ropes, whether this would ever be experienced in practice is unlikely, personally it is a risk I would accept since ruining the rope is far preferable to dying. None of the other "assisted braking" devices have ever produced enough braking force to begin to damage the rope. The Climbing Technology devices are the only ones I would consider using but I don´t.


I didn't see any mention of the GriGri. Do you know if a GriGri holds, and does it damage the rope to the point of shredding/breaking it, at the FF2 forces?
Brian
From North Kingstown, RI
Joined Sep 27, 2001
430 points
6 days ago
anotherclimber wrote:
dino74, That is excellent! Thank you for passing on your trick to finding those things. Jim Titt, You are a wealth of information good sir! I'm very appreciative of you contributing here and you've answered a lot of my questions. To continue the conversation... We can agree that with no hands on the brake strand in a loss of control scenario in a high fall factor, the Megajul and Smart Belay are not going to hold. Then again, neither are the ATC XP, BRD, and Reverso 3, so there is no advantage there for any of the devices. But what about when there is full brake hand control of the brake strand? Even with gloves on losing 20% of grip strength, if the assumption is that 22kg of brake hand force is near the high end of what people can realistically do, you're still at 17.6kg which seems to be acceptable according to the information you provided with the Italian CAI (assuming I interpreted what you were trying to get across correctly). Especially since the Megajul and Smart Belay's curve flattens out at the top end there is not a large difference in belay force between 22 and 17.6 hand force. Oddly enough, this puts the Megajul, Smart Belay and Reverso 3 at about the intersection of each other in belay force. Is this still not enough belay force for catching factor two falls without unacceptable amounts of rope slip? Which begs me to ask the question, what it the minimal acceptable amount of belay force provided from the belay device needed with full brake strand control to catch a fall factor two with an acceptable amount of rope slip? And wouldn't some rope slip be ok to reduce the violence of the impact of the catch on the rope, gear, anchor, and climber? It also just occurred to me... Does the belay force of any given belay device double, or at least increase significantly when using twin or half ropes compared to single ropes in a factor two fall since both strands will be catching the climber? This would seem to be a simple solution to the problem if it were so. Thanks again. I'm grateful for the time and effort you put into contributing here.


I wouldn´t have described the hand force the Italians use as "acceptable", it´s their opinion of what is reasonably achievable by a large proportion of the climbing community. The 25kN used by the DAV/UIAA is the value obtained from a lower proportion of climbers since it was an average.
The chart from my tests stops at 22kN as this is the maximum I can achieve with this rope. The range of tested grip strengths ranges from 7kg to 45kg depending on the rope and the test candidate. With a giant furry rope I´ve got 40kg.
For a moderate FF2 it´s around 2.5kN, longer falls both FF2 and highish factors like 1.9 you want more. Acceptable slip is around 1.5m to 2m with an ungloved hand. What´s acceptable with a gloved hand is a matter of the terrain below.
A braking force of 120 kg or so is completely unnaceptable, it´s not much more than I weight with a full load of gear on sometimes!
It´s worth remembering that traditionally one was taught to bring both hands down onto the braking strand in the event of a possible fall which helps matters considerably, this no longer seems to be standard practice.
The use of twin/half ropes is below, these are to the maximum until the rope starts to slip through my hand to show the effect of equally loaded (twin rope technique) or half-rope use where one strand takes the load.

Rock Climbing Photo: Testing two strands
Testing two strands


I climb with 7.8´s and use either 2 or 3 karabiners in an ATC XP which gives acceptable results, an option which generally "assisted" devices do not have. Somewhere I´ve a test table of the results.
Jim Titt
From Germany
Joined Nov 10, 2009
0 points
6 days ago
anotherclimber wrote:
Thank you. That must have slipped by me on subsequent reads of his post trying to absorb and understand it. That's rather a scary thought that with the exception of the Grigri, the ATC XP is the only one remotely capable of catching this sort of fall.


There might be others, I don´t test every obscure plate just the common ones! The Metolious BRD outperforms the ATC XP sometimes, other times not, with thin ropes it´s not real good though some vee grooves would help a lot. The DMM Pivot/Mantis is also a good performer, second best to the ATC XP in my testing.
The GriGri or more specifically the GriGri 1 will stop any fall without damage to the rope, I use it as the rope lock on the other end of the tester. At very high loads it may jam in the locked position but after freeing-off it´s fine. I´ve routinely loaded one to over 7kN with no rope issues, there is deliberately a gap between the cam and the end plate when it is fully locked to prevent the rope being cut.
Jim Titt
From Germany
Joined Nov 10, 2009
0 points
6 days ago
climbing friend titts,

would you tell the germans to improve upon the mega jul, so it truly becomes one device to rule them all, one device to belay them?

perhaps it will not kink the rope? Perhaps they will make it so that you do not receive the dirty look from others at the sport rocks or meat cave if you show up without a grigri?
Aleks Zebastian
From Boulder, CO
Joined Jul 3, 2014
178 points
6 days ago
Jim Titt wrote:
I wouldn´t have described the hand force the Italians use as "acceptable", it´s their opinion of what is reasonably achievable by a large proportion of the climbing community. The 25kN used by the DAV/UIAA is the value obtained from a lower proportion of climbers since it was an average. The chart from my tests stops at 22kN as this is the maximum I can achieve with this rope. The range of tested grip strengths ranges from 7kg to 45kg depending on the rope and the test candidate. With a giant furry rope I´ve got 40kg.


Thank you for the clarification on grip strength. That does vary quite more widely than I initially thought.

Jim Titt wrote:
For a moderate FF2 it´s around 2.5kN, longer falls both FF2 and highish factors like 1.9 you want more.


Are you still measuring brake hand grip strength here? And if so, why did the value change from kg to kN?

Jim Titt wrote:
Acceptable slip is around 1.5m to 2m with an ungloved hand. What´s acceptable with a gloved hand is a matter of the terrain below.


Good information, thank you.

Jim Titt wrote:
A braking force of 120 kg or so is completely unnaceptable, it´s not much more than I weight with a full load of gear on sometimes!


While I get this... I struggle to understand why I've never seen my Smart Belay slip rope on unintentional hard catches. I'm guessing that even with a hard catch it's never gotten to that point yet?

Jim Titt wrote:
It´s worth remembering that traditionally one was taught to bring both hands down onto the braking strand in the event of a possible fall which helps matters considerably, this no longer seems to be standard practice.


Good point! So double, or at least added grip strength over one hand. Oddly enough I make sure my belayers do that for all falls regardless of the belay device and for lowering with non-brake assisted devices. We practice with ATC's occasionally in the gym to stay sharp with good belay technique. It's easy to get sloppy and complacent using brake assisted devices all the time.


Jim Titt wrote:
The use of twin/half ropes is below, these are to the maximum until the rope starts to slip through my hand to show the effect of equally loaded (twin rope technique) or half-rope use where one strand takes the load. I climb with 7.8´s and use either 2 or 3 karabiners in an ATC XP which gives acceptable results, an option which generally "assisted" devices do not have. Somewhere I´ve a test table of the results.


Now this chart and data is truly interesting! And reminds me of what I had read from other posts of yours showing how the diameter of the rope played into how well it catches. It's also interesting that it is not anywhere near double belay force for two ropes, although it is increased. I also find it interesting that 8.5mm half or twin ropes on a Smart Belay gets almost as much belay force as the ATC XP more with the single than double, and compared with the 9mm single rope on ATC XP, double 8.5mm ropes on a Smart Belay gets almost the same belay force. Do you find this configuration sufficient in stopping power? It's pretty messed up to think that you can't necessarily trust that any rope you use within the advised range of a device won't give near or similar performance in stopping power.

With the exception of using a Grigri with a single rope that's wider than 8.9mm that you can test yourself to make sure it locks up each time, there doesn't seem to be any easy answer beyond avoid factor two falls at all costs. Which should be done anyway, but accidents and mistakes do happen.
anotherclimber
Joined Apr 4, 2016
57 points
6 days ago
The 2.5kN is the force you want to generate with the belay device. Or more if possible!

The ranges given for rope diameter have often enough been critisised on here and elsewhere.
The difference in braking effect from varying rope diameter is considerable, here´s one of Bill Stronge´s graphs which shows the wild variations possible:-

Rock Climbing Photo: Hand Force & Rope Diameter
Hand Force & Rope Diameter


Sometimes devices have peculiar sweet spots or weaknesses, typical are things like the Reverso series where one particular rope diameter fails to go down into the braking vee grooves at low hand forces so you see a peculiar result. The Smart has slightly different curves than the MegaJul even though they are effectively identical due to the shape of the rope relief slot (these types of device need to stop the karabiner coming against the body where the rope clamps as otherwise they jam up completely and it´s impossible to pay out rope again), the Smart it´s a flattish slot whereas on the Mega Jul it´s half round. The relief slot on the MegaJul is far too big for thin ropes, under load 7.8mm ropes are not jammed in any way by the karabiner i.e there is no assistance to the braking.
Jim Titt
From Germany
Joined Nov 10, 2009
0 points
6 days ago
To go beyond all the charts and graphs, get back to the original thread, and put this in perspective. I think I’m on pretty solid ground making the claim that most belay accidents happen because of human error while cragging and gym climbing. That is where most of the inexperience lies. This is where assisted belay devices are useful no matter what brand you prefer. This is the wave of the future if you look at all the new belay devices being introduced at the 2017 trade show. Thanks to all the left brain people they will get better. Factor 2 falls are thankfully rare yet it dominates the thread down to the minutiae as to which device holds a F2 better. It looks like most belayers can’t hold one anyway. So I'll use an assisted belay device while sport cragging/gym climbing as it is way more comfortable when my fat partner is hang dogging and use my ATC XP Guide while multi-pitch trad climbing. The ATC XP Guide is much easier to pull rope through in guide mode anyway (than the MegaJu at least). And don’t use super skinny ropes at the low end of the accepted range of the device. Brian
From North Kingstown, RI
Joined Sep 27, 2001
430 points
6 days ago
If I am belaying a potential FF2, I pull up 20-25 feet of rope downstream of my brake hand and either put a loosely tied knot or a clove and a biner in the line, so if I fail to arrest, it jams against the belay device. I can shake this out one handed. A frequent poster to this thread has previously said this is not a good solution, but it works for me. I have also posted the idea of of relocating the belay to lower down at times, or placing a first piece in the second pitch before bringing up the second, but I am almost always on doubles.

Luckily in forty years of climbing, the only time I have had to arrest a fall with nothing in, it was not straight on,the leader moved up and off at an angle.
Tom Stryker
Joined Aug 24, 2014
257 points


Follow replies to this topic? Notify me at the top of web site.
1

Email me.
Page 10 of 14.  <<First   <Prev   8  9  10  11  12   Next>   Last>>