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tokyo bill
Social climber
tokyo
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Aug 17, 2009 - 06:28am PT
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Well, I feel like I'm playing tennis with myself, but here's the relevant stuff from that report, so far as I can tell.
First, description of the "Dynamic performance" test that they used (p. 40):
"Peak impact force and slippage with a fall factor 2 drop with a 100 kg mass.
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Perhaps the most relevant test, this test investigates the energy absorbing abilities of the devices in a worst-case scenario: a fall factor 2 with an inelastic lanyard."
And then their comment in the Ushba's performance (p. 43):
"The Ushba 'Stop-Lock' fared very badly in the dynamic tests. Only two devices were available for the dynamic tests and both of these cut the rope completely, without any slippage, at a peak force of 5.5 kN. The devices were too distorted and damaged to test again. This would appear to be a serious design fault and the Stop-Lock cannot be recommended for use as a back-up device. No further tests were carried out."
My interpretation is that they had two Ushbas. They subjected both of them to a dynamic test in which they did fall factor 2 drops with 100 kg weights by attaching the device to a rope, and a 100kg weight to the device via a 1 meter long static lanyard. In other words, 100kg weights were dropped the two meter length of the lanyard, and then hit the rope. The Ushbas cut the rope and got trashed, with maximum forces recorded before cutting of 5.5 kN. Having trashed the available devices, they did no further testing.
I'd be interested in other opinions, but my reaction is that this test isn't a particularly accurate simulation of TR solo use. It actually sounds more like a test for a lead solo device. It gives added emphasis to the need to keep slack out of the system in a TR solo rig; but presumably folks who TR solo already know this.
Could the Ushba have come away with an inaccurate reputation for general rope cutting due to imprecise reading of this report?
Thoughts from anyone?
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Rankin
climber
North Carolina
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Sep 30, 2009 - 08:42pm PT
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Bump for one of the coolest threads on the Taco. I've been using a Mini Traxion as shown in the photo of Kauk's set-up for the last couple of days. Took me a couple runs to dial it in and get comfortable with it.
Wow, what a game changer! Thanks to Chris Mac for providing such a wealth of info on the Taco.
I'm only using one Mini right now, and I don't see a need for another one, but I would also be curious if anyone has experienced any Mini Traxion slippage or failure in the top-rope set-up shown here. Also, I found that I needed to weight the bottom of the rope to get the device to run smoothly. I just clipped my shoes to the rope, which seemed to be more than enough weight.
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mongrel
Trad climber
Truckee, CA
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Sep 30, 2009 - 09:36pm PT
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Whoa, Majid_S, let's keep the record straight, the info that appeared on this site, specifically including accident analysis by the Zion SAR or rangers or whoever is the appropriate authority, was that the accident resulted from shock-loading of the Pro, the climber having been jugging on a rope threaded through the Pro and loaded by the haul bag. You can search for the whole thread and get all the details. The Pro-trax may or may not be a crummy device; who knows more about hauling than PTPP? The point of this post is not whether it's good or not, but that, regardless of the quality of the gear, if you do stupid or unsafe scheisse, you will very likely end up dead in a hurry. Be smart and use things right and they won't break and you won't die from a bonehead accident (just maybe another kind - but much lower frequency of those).
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adkeditor
Trad climber
Saranac Lake, NY
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Aug 15, 2011 - 06:59pm PT
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Reviving an old thread ... I am interested in solo top-roping and have been reading threads on various sites. A lot of people recommend Petzl's Mini Traxion, but Petzl now recommends against using it for this purpose. Instead it recommends using an Ascension and Basic for single strand top ropes and the Ascension and Microcender for dual strands. Has this changed people's opinions of the Mini Traxion?
The following is from Petzl's website:
"Use of the MINI TRAXION pulley: Warning:Petzl has studied the current usage of the MINI TRAXION as a self-belay device on a fixed rope. Serious accidents and many handling errors have been reported.
"The risk of using the device with the cam held open is significant, as well as the possibility of accidental opening of the cam when climbing.
Consequently, Petzl no longer authorizes the use of the MINI TRAXION for self-belay, even when combined with a backup."
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sac
Trad climber
Sun Coast B.C.
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Aug 15, 2011 - 07:35pm PT
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Been using this rig for 15 yrs.
Never failed.
Very little friction on 10.5mm.
Heard they stopped making them, prob some out there.
An important function for me is to "release" the device after load.Or rapping.
This one simple, un-wieght slightly, rotate device, and hold, and lower, w/ rap device, kinda like a prussic, but easier, more simple.
Not so easy w/ mini-tax imo.
cheers.
A.Durie.
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tolman_paul
Trad climber
Anchorage, AK
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Aug 15, 2011 - 08:03pm PT
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I guess I'm the only person using a soloist, and have been for over a bit over 20 years. Yes, it is a specialized piece of gear and not cheap, but considering the alternative of using a device not really designed for the application?
The soloist is super smooth for top roping, I've used it with 10, 10.5 and 11mm ropes. You should coil your slack rope so that it hangs to provide a little bit of weight and it'll self feed easy peasy.
Simple, lots of surface area to grab the rope, no teeth on the cam.
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steelmnkey
climber
Vision man...ya gotta have vision...
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Aug 15, 2011 - 08:08pm PT
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Been using this for a little over 20 years. Never failed.
Always liked it because of the foolproof design and machined rope interface.
Once you have it locked on the rope properly, it's there to stay.
I've climbed solo on a Soloist, Silent Partner, Microscender, Mini Traxion, and Gri Gri at one time or another. All have pluses and minuses.
Truth be told, (IMO, of course) just about any of these devices are okay to use as long as you climb conservatively and follow basic survival rules. People always seem to want a device that is guaranteed to catch them if they're huckin' mo's 1000 feet up the side of El Cap and if you're doing that sort of stuff, you're way better off having someone that cares about you hangin' on to the other end of the line. Doing crazy sh*t out there while solo climbing might be extreeeeeme and all, but it's not a good way to stack the odds in your favor. Obviously not advice for the vets, but some thoughts for the nOObs looking for info.
T_Paul - are you using the Soloist for TRing?
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The Mayor
Social climber
Billings, Montana USA
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Aug 15, 2011 - 11:36pm PT
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I've been using the Soloist for TR'ing 20 plus years and literally thousands of falls. No complaints.
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mctwisted
Social climber
superslacker city
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Aug 16, 2011 - 01:19pm PT
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this is a setup like the one posted earlier with the pics only with the microsender on top and basic ascender on bottom. so in the event of a small fall there would be less trauma on the rope (as the micro cam is more gentle than the toothed ascenders).
i bought the micro years ago for rigging work because we had used them to pull large loads without damaging the rope (not as good as prussik, which is used by yosar for raisings on el cap).
i tried most of the mentioned setups and feel most comfortable with this one, and i think all of the mentioned double devise setups are good as long as there is no slack developed! which requires a shoulder sling or chest harness to keep the upper devise up high so if you come off you don`t take a 6" fall, and also a weight on the bottom of the line to outweigh the friction of the devises down low on the climb. i have seen tractioners take these little falls at the cookie cliff, and it seems brutal on the rope. as mentioned in other posts keep cool and in control, and take in extra slack if your going to come off( this is best done by pulling on the rope above you and sucking it through the devise, rather than below as it would be if you were to "take" a leader.
you will probably notice this micro has seen alot of use and the cable has been replaced with weed whacker cord, which i prefer to the cable (i think the arborists came up with that one) works good and provides more spring tension. and as mentioned in other posts keep any loose shirts or chalk bag straps or cords away from system so there is no unforeseen complication that threatens your saftey
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steelmnkey
climber
Vision man...ya gotta have vision...
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Aug 16, 2011 - 03:12pm PT
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Never liked the way it looked like the rope had to do a coil around the Soloist to be aligned right. Seemed like it would really mess with the smooth feed of the device. Maybe I better take another look.
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tolman_paul
Trad climber
Anchorage, AK
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Aug 16, 2011 - 03:32pm PT
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Just coil the slack at the base of the climb so that it hangs and the soloist will feed very smoothly. I used to use it to do laps on favorite routes and I never had issues with it feeding.
One other plus of the soloist. Say you're doing a slightly overhanging climb, you peal or burn off and find yourself free hanging. With the soloist you just grab the slack end of the rope, lean back until it starts to free itself and rap to the base of the climb. If you're using an ascender or double ascender you're going to have to rig up a rap device and remove the ascenders to get down, or pull out the aiders and jug to the top.
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The Mayor
Social climber
Billings, Montana USA
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Aug 16, 2011 - 06:45pm PT
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You can do that on vertical rock also, a good way to work moves or sections.
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pFranzen
Boulder climber
Portland, OR
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Aug 16, 2011 - 07:56pm PT
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Could someone re-post the picture of the Kauk setup? The original in dingus' post is broken.
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mikeyschaefer
climber
Yosemite
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Aug 16, 2011 - 09:29pm PT
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I've used the pro-trax and mini-trax for TR soloing since they came out. If I was to guess how many feet I've climbed with them I'd say close to 75k and hundreds of days of use. And as far as falling goes on them I can't even count. I've taken repeated falls on the exact same section of rope over and over and over while working projects or FA's. Never once have I seen ANY damage done to the sheath. Not a bit. I generally use a medium stretch static these days (%3 or so) but have also used dynamic but don't like them nearly as much. It seams like most people I know in Yosemite choose to rig some sort of chest harness but I've tried using them but I find it gets in the way if you are really working moves at your limit. I guess my comfort level is high enough that I don't mind taking the additional 6" fall on them.
I always use two of them but rig the lower one on a different tied belay loop that is longer than the factory harness belay loop. This keeps the device slightly apart when climbing and when falling on them.
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okie
Trad climber
San Leandro, Ca
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Aug 16, 2011 - 09:50pm PT
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I wonder how strong that little axle pin is on the pulley wheel of the minitrax? Man, if that thing broke and you were only using one...
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Chief
climber
The NW edge of The Hudson Bay
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Aug 16, 2011 - 09:51pm PT
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Great thread and important topic as this technique is gaining popularity.
I don't climb as much these days much less solo top rope.
Did some solo big walls in the old days with some rigs that horrify me now.
Last couple outings were with a Soloist and it seemed to work well and even held a couple gnarly falls.
I do use a variety of rope grabs in my rope access and rigging work and we're still looking for the best device.
At the risk of preaching to the choir, here's a few thoughts.
Most rope grabs damage the rope at some point and it's a function of impact force. There's anecdotal and empirical evidence that toothed ascenders and Ushbas are the worst and Rescuscenders and Microscenders not as bad. Petzl has done a bunch of testing as has Kirk Mauthner at Rigging for Rescue.
We've been using the ANSI approved DMM Buddy recently and it seems to work well trailing on back up ropes both ascending and descending.
We also run the precaution of attaching to it with a short Petzl shock pack.
I wonder if anyone's trying it for solo toproping?
As a general rule, I'd be concerned about two things solo top roping;
1) Impact force on the device (and the climber!) and resultant rope damage (which could be mitigated with a shock pack).
2) Integrity of the connecting hardware and prevention of cross loading and roll out.
I like the idea of a second device for redundancy and wonder if that might be as simple as pushing a separately attached prusik upstream of the primary rope grab? Sounds like some are doing this?
In any event, it's incumbent on the user to do their homework, recognize the risks and engineer a system that works best for them. There's lots of good information available and this thread is a good start.
Best,
PB
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Abe Froman
Trad climber
NY, NY
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Sep 19, 2011 - 03:55am PT
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I've looked through several of these threads about different devices. I think I've settled on the Microcender. Is anybody out there using a Klemheist as a backup instead of a prussik (I believe the Klemheist would slide up the line more easily) or a second device? Thanks.
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HuecoRat
Trad climber
NJ
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Sep 19, 2011 - 08:09am PT
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Over the years (30 of them) I have used:
Gibbs Ascender
PROS
Easy to use
Locks off instantly
(with spring attached)
Can be used for leading
Easy to load/unload
CONS
Does not feed easily (Rope must be weighted below)
Eye is not intended for shock-loading
Mini Traxion
PROS
Easy to use
Stronger than Gibbs
Feeds smoothly!
Easy to load/unload
CONS
Cam can lock open (just watch to be sure)
Soloist (Wren Industries)
PROS
Strong! Specifically designed for this
Zero rope damage
Great for leading
CONS
Slow to feed at the start
Requires chest harness
So, after years of rope soloing, for solo TR I go with the Mini Traxion. For solo leading I go with the Soloist.
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ClimbingOn
Trad climber
NY
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Nov 27, 2011 - 06:06pm PT
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moosedrool, the problem with the cinch is that it requires a backward fall (away from the rope) to properly engage. If you fall straight down, the camming action may not engage. This has occurred in testing, and is disturbing when thinking about using it to TR solo. Try it on a fixed rope to see what I mean. The mini traxion does not suffer from this problem. If you are intent on continuing to use the cinch for this application, make certain you continue to use a backup prussic.
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ramonjuan
climber
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Nov 27, 2011 - 11:03pm PT
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I use two mini's off the belay loop. On the top one I used a dremel to cut out the part of the frame that locks the cam open and use a auto locking dmm oval. This is connected to two crossed over the soulder slings with some accessory cord. On the bottom one I clip it to the belay loop as well as the main loop of a sterling chain reactor using a regular screw gate dmm oval. I fall on this set up all the time and have never had a problem. I'd post a pic of the dremel work but I haven't figured out how to do it from my iPhone yet.
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