UKC

Assisted Lockers and Half Ropes

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 Bobbyjames 17 Feb 2021

Hi,

I'm thinking about buying an 'auto-locking' belay device to use with my half ropes (8.6mm Beal Cobras).

What concerns me are the comments floating about which talk about devices like the Jul slipping at higher fall factors, or not holding decent falls onto a single half rope. I don't know how true these statements are, or whether or not they apply to the Mega Jul and/or Micro Jul.

I am aware of the test that was posted somewhere, which seemed to say the (Mega?) Jul was fine in typical 'soft' usage, but the design didn't provide brilliant results in high fall factors. I don't think there was any mention of other less than ideal situations though?

Could anyone share some experience/comments on using the Micro Jul or Alpine Up where someone has taken a reasonable fall, perhaps onto a single half rope? Or can anyone point me in the direction of some decent tests that have been conducted, which might shed some light over subject?

I understand larger falls and dropping onto a single half-rope is generally to be avoided. The question is more focused on how these devices compare to each other and against an ATC, in these circumstances. 

Thanks.

In reply to Bobbyjames:

if your Trad'ing id use a ATC/Guide end off!

 Bobbyjames 18 Feb 2021
In reply to Paul Hy:

Yes, you might prefer an ATC and it may very well be the safest and most versatile option going. It's certainly the most common!

The above question still stands though. Do the current auto-lockers function in those scenarios.

 jimtitt 18 Feb 2021
In reply to Bobbyjames:

Well I did the testing and the results independently confirmed by Cambridge University Engineering Dept so yes they are true. The MegaJul which I tested is replaced by the GigaJul which probably isn't much better but not tested, the MicroJul has never been tested. The Smart is due for replacement. The AlpineUp is excellent. The tests are on Mountain Project, search for the MegaJul threads.

Be aware also that if only one strand of a pair is loaded the braking is seriously compromised even with an ATC.

 C Witter 18 Feb 2021
In reply to Bobbyjames:

There are a few different issues condensed here, which you might want to read up on.

First, is terminology. The devices you mention are assisted-locking devices - not "auto-locking" devices. Therefore, these devices are not expected to catch a fall; they're expected to assist the user in catching a fall by increasing the friction.

Second, when using trad gear, you want a dynamic catch. This is in order to lower the forces on the gear itself. In this scenario, slippage is desirable! An ATC/tube-type device allows a degree of slippage which lowers the forces involved. Note that Edelrid advise using their jul devices on bolted climbs, and only when a degree of dynamic belay ban be introduced by the belayer being able to move, rather than belayed to the rock: https://media.edelrid.de/images/attribut/54544017_GAL_MegaJul_MicroJul_MegaJulSport_SS_161205.pdf

The Alpine UP gets around this by basically turning off the assisted braking: https://www.climbingtechnology.com/en/outdoor-en/belay-devices/manual-braking/alpine-up The question is, why would you want to cart 175g of metal up to do what 40g of metal can do? Specialist applications, maybe.

Only then do you get into discussing catching on only one half-rope - and I'm not entirely sure what you mean here, i.e. whether you mean belaying a second or a scenario where you've decided only to use one half-rope to lead. Catching a second, the forces will be very low and there's no real issue. Catching a lead fall, it goes without saying that if you're expecting the leader to fall, you should be using the half-ropes as a pair. Otherwise, there will be less friction so it will be more tricky to catch. None of this particularly relates to the difference between an ATC/Micro Jul.

Post edited at 11:42
 Cameron_S 18 Feb 2021
In reply to Bobbyjames:

I've been using the climbing technology alpineup for a couple of years now for all my climbing and have found it brilliant. 

For trad it has locked really well when holding falls including on an individual 8mm mammut half rope when I pinged off with only one piece in. I also like the fact you don't have to use a prussik when abbing.

There are a couple of downsides with it however, on fat single ropes it locks too easily when giving a lot of slack quickly, it's much bulkier than an atc, I find installing the rope when wearing gloves a pain but possible. 

Overall I'm very pleased with it, much prefer it to other ABD that I have used. 

In reply to Bobbyjames:

I've used a Microjul for many years now - I think this will be the 8th year I've had it. I use it alongside a Petzl Reverso, and ATC Guide, and DMM Pivot, along with a first generation Grigri.

It was Jim Titt who post regularly here I think who tested the Microjul and found this thing of it slipping more readily at high fall factors. I must say I've never noted anything like that just standard use - but I fully accept Jim's research, so it just kind of reinforces the issue of trying not to get into the position of holding a fall directly onto the belay on a multipitch for example - get a runner in to protect the belay as soon as you can etc. although I wouldn't NOT do that if I had taken my ATC Guide with me that day.

There are certain advantages with the Megajul, it's light, it is "assisted locking" in effect - not a bad feature when winter climbing and after an hour of belaying in poor weather you might not be paying quite as much attention to an out of sight leader as we know we should in perfect world. I also find the locking abseil function works well although Edelrid seem to have backed off recommending that. It is also more fiddly to pay out and easier to short rope your leader if they suddenly try to yank out some slack - like using a Grigri in that respect.

I have held falls with it, but normally using double ropes and nothing memorably spectacular - but in the years and hundreds of climbs I've used mine for I've never had any problem holding a fall, rather the opposite - it holds falls in normal conditions very well.

 C Witter 18 Feb 2021
In reply to Bobbyjames:

p.s. I think this is Jim Titt's graph: https://cdn2.apstatic.com/forum/50692.jpg

If I'm reading this correctly, the catch on one half-rope with an ATC is only marginally below the catch of a Jul on two strands. Which, if this is the case, only confirms how pointless the Jul is...

Post edited at 11:54
 AlanLittle 18 Feb 2021
In reply to jimtitt:

> The AlpineUp is excellent.

I'm a satisfied user of the bulky-looking and highly unfashionable Alpine Up.

 Ciro 18 Feb 2021
In reply to C Witter:

> Only then do you get into discussing catching on only one half-rope - and I'm not entirely sure what you mean here, i.e. whether you mean belaying a second or a scenario where you've decided only to use one half-rope to lead. Catching a second, the forces will be very low and there's no real issue. Catching a lead fall, it goes without saying that if you're expecting the leader to fall, you should be using the half-ropes as a pair. Otherwise, there will be less friction so it will be more tricky to catch. None of this particularly relates to the difference between an ATC/Micro Jul.

On a wandering route near your limit, would you  bring both ropes along the line of the route, rather than limiting drag by only clipping one of the ropes when far left, and the other far right?

I've taken a fair few catches on sea cliffs in the above scenario, where only one rope got tensioned, with standard tube devices and the alpine up in dynamic mode, and never felt I was in danger of losing control of the rope.

Also, on grit I've taken falls with only one piece in and been held by my belayer without issue.

 C Witter 18 Feb 2021
In reply to Ciro:

Yeh, me too. And Jim Titt's graph actually seems to support this not being a massive issue, though apparently it can lesson catching force by up to 40%.

 C Witter 18 Feb 2021
In reply to C Witter:

Two dislikes - apparently for citing proper use as defined by manufacturers...?

 jimtitt 18 Feb 2021
In reply to Ciro:

> Also, on grit I've taken falls with only one piece in and been held by my belayer without issue.


It's worth bearing in mind when we test climbing equipment we look at worst case. A fall on grit (and nearly all UK cliffs) is by definition small compared with what's possible with a 60m rope.

In reply to TobyA:

Sorry, I meant Megajul not micro! Mixing up the two.

 Rick Graham 18 Feb 2021
In reply to jimtitt:

> It's worth bearing in mind when we test climbing equipment we look at worst case. A fall on grit (and nearly all UK cliffs) is by definition small compared with what's possible with a 60m rope.

Exactly.

Hardly any climbers will have to hold a factor 2 fall in their lifetime .

 cambromo 18 Feb 2021
In reply to Bobbyjames:

I've got the alpine up but I've had near to no experience with it in a trad setting since lockdown has happened. It seems a bit fiddly using it in guide mode compared to using the pivot however twin ropes at 8.0mm holds fine locked off, however I haven't caught a fall with it yet.

Besides just hold the brake end, what's the issue?

In reply to jimtitt:

> It's worth bearing in mind when we test climbing equipment we look at worst case. A fall on grit (and nearly all UK cliffs) is by definition small compared with what's possible with a 60m rope.

But, on the other hand, the fall factor is likely to be higher than on a 50m pitch. Although obviously the ground prevents it being bigger than 1.

 jimtitt 18 Feb 2021
In reply to Robert Durran:

"Likely" doesn't come into consideration nor does the fall factor except for the need for the belayer to change their hand position. Likely isn't worst case and an FF2 can occur on any multi-pitch route if your unlucky. We look at the energy that can be absorbed by the belay system.

In reply to Bobbyjames:

I'm a big fan of the Mega Jul (and have bought one for a number of my regular climbing partners under the guise of a present but with a view to keeping them and me safer ;-)) I especially like the assisted belay and the 'prussik-replacement' function when rapping.

However, I have experienced a worrying 'fall catch' using one which I think is worth sharing. This was with a pair of Mammut 8.0mm half ropes, one of which was brand new, somewhat shiny, the other a bit fluffier . Basically the fall was with gear on only one rope - the new shiny one (run-out crux protected by a bomber thread) and despite an attentive belay by me (it was my son on the sharp end!) a LOT of rope went through despite my holding the rope OF COURSE! (with a bit of a rope burn in consequence). it almost seemed that the older, thicker rope 'held off' the breaking function.

I was so concerned that I contacted Edelrid, and they pointed out that while the website (and indeed the label on the device) says >= 7.9mm ["Approved rope diameter [mm]: 7,9 - 10,5] see https://www.edelrid.de/en/sports/brakingassist-tubers/mega-jul.html

...if you consult the actual data sheet it states that this is for TWIN ROPE use only - the figures for using as half ropes (ie the typical UK trad set up) is >= 8.5mm. see https://media.edelrid.de/images/attribut/54544017_GAL_MegaJul_MicroJul_MegaJulSport_SS_161205.pdf

I suspect I'm not alone in not always reading the datasheet - especially when the wider range figure is quoted on the website and on the label!

I now use a micro-Jul for these skinny ropes and haven't had a similar issue [6.9mm for twin ropes / 7.9mm for half ropes]

 rgold 19 Feb 2021
In reply to Bobbyjames:

For half ropes specifically, I don't think there is anything better than the CT Alpine Up.  I've used it almost exclusively for many years now, I think since soon after it came out, mostly with Mammut Genesis 8.5's, and have caught numerous "ordinary" leader falls and one really long one with it, all catches on just one of the two strands.

I've tried most of the other brands and consider the Alpine Up to be superior for the tasks of handling half ropes, specifically managing the need to take in and pay out almost simultaneously.  Many of the other devices (Edelrid Juls and Mammut Smarts) trap the brake hand in a release loop or lever in order to pay out slack, leaving the other hand to frantically alternating between pulling in one strand and pumping out the other.  Yes, if there is little rope weight, those devices can sometimes be handled in more ordinary fashion without locking up and short-roping the leader, but the Alpine Up is better, more hassle-free, and if you are used to any kind of ordinary belay plate, more intuitive.

I must say that sometimes threading the UP can be a bit of a struggle, especially if you are using it to belay a second and so are fighting rope weight, or are setting up a rappel.  I worry about dropping it, although I never have.  In critical situations, it can be clipped back to you via a sling clipped to the hole used to unload the device when it is being used in guide mode.  This attachment doesn't interfere with threading the device.

It can be a little hard to get going on rappels with my 8.5's; I often have to feed the ropes into the device for the first 10m or so, but it isn't hard to do and isn't jerky.  The device is very reliable about locking up if you release your grip on handle, and this even with very little rope weight below, unlike some of the other devices that start to slip in the same situation.

Friends who use it with single ropes report ok handling for sub-10mm diameters, but once the ropes get thicker there is too much unwanted locking-up.  I think it is best suited to half ropes somewhere in the 8mm range of diameters.

 Iamgregp 19 Feb 2021
In reply to C Witter:

I think it's because you corrected the terminology to "assisted locking device", rather than "assisted breaking device"?

 C Witter 19 Feb 2021
In reply to Iamgregp:

Maybe! Fair enough.

In reply to jimtitt:

> Be aware also that if only one strand of a pair is loaded the braking is seriously compromised even with an ATC.

And this will normally be the case with double ropes........

 wbo2 20 Feb 2021
In reply to Iamgregp/C.WItter: I'd prefer an assisted braking device to an assisted breaking device

Although the latter may be true

Post edited at 07:33
In reply to Iamgregp:

> I think it's because you corrected the terminology to "assisted locking device", rather than "assisted breaking device"?

I thought it was him trying to suggest the use of half ropes as dangerous if you're expecting the leader to be caught on only one strand. That seems to invalidate many people's use of half ropes. Perhaps you were talking about people only using one strand of a pair of half ropes but it wasn't clear.

 Iamgregp 20 Feb 2021
In reply to wbo2:

Ha!  You might have a point there!

 Rick Graham 20 Feb 2021
In reply to jimtitt:

> "Likely" doesn't come into consideration nor does the fall factor except for the need for the belayer to change their hand position. Likely isn't worst case and an FF2 can occur on any multi-pitch route if your unlucky. We look at the energy that can be absorbed by the belay system.

One quirk of the understanding of fall factors and maximum forces is the following theoretical scenario.

Using 50 metre ropes ( to keep the maths simpler) if a leader falls without runners on a multi pitch route.

If the leader falls from 5 metres above the belay , the fall factor is 2.0.

If the belayer lets go of the rope, the leader will fall 55m ignoring stretch and the fall factor is only 1.1!

Just being a bit provocative but I have been involved in both scenarios in 50 years of  climbing .  Each time it was not pretty but no permanent damage somehow.

 Iamgregp 20 Feb 2021
In reply to timparkin:

I did wonder about that, but I’ve never used half ropes so didn’t know if I’d understood correctly 

 jimtitt 20 Feb 2021
In reply to Rick Graham:

Do you somehow think I don't understand fall factors?

 Rick Graham 20 Feb 2021
In reply to jimtitt:

Just getting your attention

As i understand it , the fall factor will indicate the maximum loads in any scenario.

Presumably in the 1.1 case the energy to the absorbed is far greater due to the longer fall but because of  the lower fall factor compared to the 2.0 case , the maximum loading is less. This conumdrum is true but only because the  load in the 1.1 case is spread over a longer timespan.

 Rick Graham 20 Feb 2021
In reply to jimtitt:

In deference to your posts and information on here , I am continuing with  my ATC xp and ATC guide. I have a gri gri and click up but they tend to rarely get used.

 RR 20 Feb 2021
In reply to Bobbyjames:

Does anyone have test info and personal experience with the Edelrid Giga Jul.

In reply to Rick Graham:

> Using 50 metre ropes ( to keep the maths simpler) if a leader falls without runners on a multi pitch route.

> If the leader falls from 5 metres above the belay , the fall factor is 2.0.

> If the belayer lets go of the rope, the leader will fall 55m ignoring stretch and the fall factor is only 1.1!

Interestingly, letting go of the rope (or indeed having any slack in the system) only decreases the fall factor if the fall factor would have been greater than one without letting go (ie the climber would have fallen below the belayer before the rope went tight. Otherwise letting go or having slack in the system will increase the fall factor. A nice bit of algebra proves this!

 jimtitt 20 Feb 2021
In reply to Rick Graham:

The force is what defines whether the rope slips, the energy in the fall is what defines how far the rope slips and therefore whether the belayer loses control or not.

 rgold 20 Feb 2021
In reply to Rick Graham

> One quirk of the understanding of fall factors and maximum forces is the following theoretical scenario.

> Using 50 metre ropes ( to keep the maths simpler) if a leader falls without runners on a multi pitch route.

> If the leader falls from 5 metres above the belay , the fall factor is 2.0.

> If the belayer lets go of the rope, the leader will fall 55m ignoring stretch and the fall factor is only 1.1!

The second scenario requires that the rope not run under any kind of friction, otherwise the analysis is completely different.   If the belayer "lets go of the rope" but it is still running through a belay plate, the fall factor analysis doesn't apply.  But strictly hypothetically, (and forgetting about the dangers of colliding with features on a super long fall) there is no "quirk" at all.  In the second scenario, much more rope is available for energy absorbtion, so the maximum tension in the rope ought to be less. 

The "quirky" lesson of some value to climbers is that short factor 2 falls can impose very high loads on the belay system.

Another fact is that once the rope starts slipping through the belay device, the energy absorbtion mode switches to work done against friction, and then the height of the fall rather than the fall factor does matter.

Post edited at 14:29

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