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HMS
Trad climber
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Jun 15, 2010 - 07:35am PT
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In reply to Degaine: I think Jim aswered your question allready?
In reply to Trad:
(a) when used according to manufacturer's specs, the Reverso 3 is safe
No, it is not 100% safe. Skinny ropes, with a diameter in the range specified by the manafacturer cam still 'flip'. As Jim said: 'upper loaded rope forces itīs way down past the braking strand and in the end the positions are reversed so that the loaded rope is underneath and the braking rope on top'.
In reply to Ghost: there is certain range [of rope diameter] in which the Tre functions perfectly, I agree!
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JimT
climber
Munich
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Jun 15, 2010 - 08:17am PT
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That thin bit of alloy is plenty strong enough, we subsequently pulled a 10.5mm rope to destruction and the Reverso showed no signs of discomfort. The rope was trashed at something over 10,8kN when the sheath stripped where it was forced against the underside of the plate. Personally I would expect the loop to hold at least 25kN which is unnescessarily strong!
As to safety, if used as instructed the Reversoģ is perfectly safe. Petzl give clear warnings about never letting go of the rope AND never allowing slack to build in the system, both of which should be normal practice for any climber using any type of belay device. Guide plates are no substitute for careful belaying nor are they intended to allow one to cook up dinner, read a magazine, rearrange ones medical support device or whatever!
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et
climber
Bozeman, MT
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Topic Author's Reply - Jun 15, 2010 - 12:55pm PT
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After a few emails and chat with Black Diamond, I have the following information:
When using the ATC Guide properly (belaying from above and with a rope diameter greater than or equal to 7.7 mm), the rope will NEVER slip past the brake end. However, they were unable to give out any testing data.
Jim ~
This statement contradicts your data, would you care to share the set-up of your tests?
FYI
I have not contacted Petzl as they are up front in their literature for the R3 that you need a 8.9 or larger rope for a single strand.
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JimT
climber
Munich
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Jun 15, 2010 - 01:43pm PT
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Interesting, though I donīt quite get the bit about belaying from above.
The setup I used was a hyraulic cylinder pulling the end of the rope, with the plate attatched to a strain gauge and free to move. The rope end was not held in any way as we were testing how well the plates worked for roped soloing.
We first got the idea to test because doing something else I was hanging on a locked Reversoģ with an 8mm rope and jerked around a bit trying to get my foot in a prussik loop, this was enough to release the rope and drop me on the ground.
Perhaps BD would care to give us their test data?
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et
climber
Bozeman, MT
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Topic Author's Reply - Jun 15, 2010 - 02:22pm PT
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Jim ~
Belaying from above means, that you are belaying your partner (who is below) from the top of the climb.
Based on what you are saying about how you tested the device, however, it seems it does not make a difference if you are ascending a rope or belaying a partner - a kN is a kN.
It would be great if you contacted BD directly and see what they have to say. And I would say nothing about solo climbing - as that they do not advocate this use; and will focus on only that.
Cheers, Et
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Al_T.Tude
Trad climber
Monterey, CA
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Jun 15, 2010 - 09:47pm PT
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Petzl introduced the masses to plaquette type auto blocking belay devices with the Reverso. The Reverso 2 added ridges on the brake side to increase drag. Being able to bring up one second or two seconds up simultaneously autoblocked with a simple, inexpensive, lightweight device that also belays leaders on one or two ropes and allows for single or double strand rappelling was a great boon to recreational climbers.
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Next, BD released the vastly superior and as yet unequalled ATC Guide. This did everything that the Reverso 2 did only better and additionally didn't turn into a rope slicing device as it wore.
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Petzl responded with their copy of the Guide, The Reverso 3; superior to the Reverso (in most ways), but no match for the Guide. Similar devices such as the Kong Ghost have not improved the breed.
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The R3, as mentioned previously, is not authorized to block one fallen follower while still protecting an ascending second follower. This takes it out of the running as a device of choice for me.
I have tried to release the weight of a fallen second by hooking the tip of a petzl biner in the release hole as instructed by the mfr and was unsucessful. Girth hitching a Mammut 8mm thin sling through the hole, clipping it through a directional and weighting it (which is not recommended by the mfr) did work.
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If the hole were larger, one could clip any biner through it. I believe that the reason the release hole is too small to insert a biner through is to prevent accidentally rigging the device upside down resulting in a possible brake failure.
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CAUTION:
When releasing from autoblock mode to lower a second it is IMPERATIVE that you back up the belay device with a munter hitch or similar device BEFORE you even begin to rig a release cord. When the device is cocked by the release cord, it goes from full lock to freefall instantly. It is an on/ off switch. Friction cannot be modulated with this cord. That is the purpose of the PRE-RIGGED munter. If you lose your balance and weight the release cord clipped to your harness or fashioned into a foot loop and it takes 2 seconds for you to regain your footing; your partner can be free falling at 40 MPH before you release the cord and allow the device to return to auto block mode. This is assuming that there is not a kink in the release cord that prevents this or that the rope has not melted by suddenly applying the brakes on a line racing through the device.
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Of course, if bringing up 2 followers, tie off the second one before beginning this proceedure as their belay device will also be disabled
by this process.
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The only limitation I am aware of the Guide posessing is that for ropes above 10mm diameter, it produces a lot of drag bringing up seconds. After a day of bringing up 2 friends on separate 10.5mm ropes on Royal Arches, you won't have the arm strength left for the requisite 12 oz wrist curls at the Ahwahnee lounge.
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This is why in this situation I carry a Kong GiGi for brining up seconds and a BD ATC Guide or ATC XP for belaying a leader. The extra weight of 2 devices is massively offset by the lower drag on thick ropes. If you insist on going ultra light weight in this scenario you can go with just the GiGi. You will probably not be belaying a leader and if you needed to you could use the GiGi or a munter hitch.
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The OP was using a plaquette as an ascender. I find this to be the device of choice for a non-dedicated ascending device. Picking from the devices on my standard free climbing rack, it locks effectively and releases and progresses easier and with less drag than any friction knot. It grabs like a prusik and releases with less effort than a bachman knot.
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It cannot progress on a weighted line, so a friction hitch must be used above it for the second device when ascending a rope. I choose a snapheist (a kleimheist variant that uses a carabiner to facilitate easier release) for this purpose. Between the two it makes for very efficient ascending compared to other non-dedicated tools.
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If rappelling with a Guide (in XP mode only) one can switch to ascending very simply:
Allow autoblock cord already clipped to your leg loop to lock rappel. Place snapheist (or similar device) on rope just above head level. Clip this loop into belay loop on harness as a backup. Insert a locking biner into "teacup" handle of the Guide and clip and lock it to the belay loop. Unclip the HMS biner from the belay loop and you are now in Guide Mode - just the way that you would bring up a second except that the device is inverted to serve as an ascender.
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Attach a long sling(s) to the snapheist sling and stick your foot or feet through it. Remove auto block rappel back up cord that is wrapped around the rope below the Guide. Stand up on foot loop releasing tension on the Guide/ascender. Pull the slack line through the Guide. Sit down in your harness weighting the Guide and slide the snapheist up the rope.
Rinse and Repeat.
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Dr.Sprock
Boulder climber
Sprocketville
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Jun 15, 2010 - 10:10pm PT
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yeah, arre we not supposed to use the mini traxion for that?
who wants to spank my grandmother?
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Al_T.Tude
Trad climber
Monterey, CA
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Jun 15, 2010 - 10:46pm PT
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<you were ascending a rope in autoblock mode? recipe for disaster! at least use a back up knot.>
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From the instructions:
Place snapheist (or similar device) on rope just above head level. Clip this loop into belay loop on harness as a backup.
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That would be the back up knot. Pretty difficult for this device to fail as an ascender, but if you require two back ups, tie in short to back up your snapheist back up.
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These are instructions for the basic proceedure. If you wish to customize them in accordance with your own level of experience and skill and risk profile, feel free to do so. In fact that's what I did. This is not exactly how it was described to me. I played with it and modified the proceedure to fit myself. There are subtleties of execution that are not included here for the sake of brevity; such as how to execute the clipping and unclipping of teacup handle biner and HMS biner while fully weighting the system.
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Any new proceedure should be fully tested and mastered by each practicioner in a low exposure environment before use in the field.
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Dr.Sprock
Boulder climber
Sprocketville
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Jun 15, 2010 - 11:26pm PT
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<ow exposure environment before use in the field...?
good advice, we have a 100 ft redwood out front that serves well as a test bed,
if something fails, it's just,
..bang...crunch...ouch....smack...break...thud...then,
wow, those branches are weird, someting must have gone wrong, i think i'll go smoke a bowl for the pain in the main membrane,
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J. Werlin
Social climber
Cedaredge, CO
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Jun 16, 2010 - 09:37am PT
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any AMGA guys(gals) have the official company policy on this?
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et
climber
Bozeman, MT
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Topic Author's Reply - Jun 16, 2010 - 10:17am PT
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I am an AMGA guide and started this thread. To my knowledge, their is no policy.
I am in conversation with a friend who works for Rigging for Rescue. Mike Gibbs did some tests in 2009 but with rescue ropes: 9.8 to 11 mm. Here is a very interesting result:
One drop test "combined a 10mm Sterling HTP rope with the Petzl Reverso 3 plaquette device and 50 cm of slack in the system. The ropes passed each other in the slot of the Reverso 3 and the load [200 kg] went to the ground."
Despite this horrifying result, Rigging for Rescue seems to be saying that plaquette devices (R3, ATC Guide, etc.) are viable tools for "hands-free" rescue work. (Let it be known that they are not using a plaquette like a normal climbing situation, but as a back up to a Descent Control Device.)
In sum, my research so far is saying that the R3 is inferior to the ATC Guide because it clearly states that it only goes to 8.9 mm single ropes. The folks at BD told me that when using the ATC Guide properly (belaying from above and with a rope diameter greater than or equal to 7.7 mm), the rope will NEVER slip past the brake end.
I am still waiting to hear from JimT who posted contradictory results; and I will post more as I hear mor from RfR.
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Derek
climber
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Jun 16, 2010 - 10:20am PT
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There is no "official AMGA" policy. AMGA standards are not protocol driven, instead placing the emphasis on application, defined as "using the right tool, in the right place, at the right time". Plaquette devices are just one tool. There are lots of times when using one make sense. There are certainly times when it doesn't. The Reverso 3 works as advertised. Apply it accordingly. Carry on....
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Dr.Sprock
Boulder climber
Sprocketville
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Jun 16, 2010 - 10:45am PT
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i think 99 percent of the people using the R3 will never use the autobrake thing.
i still would not hang anybody i like off that big hole in the R3.
it just looks weak, gut instinct.
and two people? forget it.
if it popped and you did not have backup, then all 3 people would hit the deck, only they wouldn't be running.
autobrake seems like a bells and whistles gadget to put it over the ATC.
so for normal rap and belay and normal rope sizes, there is no difference between using the R3 or any other device as far as safety is concerned, right?
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J. Werlin
Social climber
Cedaredge, CO
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Jun 16, 2010 - 11:31am PT
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Thanks et, interesting stuff.
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JimT
climber
Munich
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Jun 16, 2010 - 01:52pm PT
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Not quite sure what you want to hear from me, Iīve posted the test results I obtained (and the test method) and they are consistent with the results for a number of other guide plates as well.
Anyone can reproduce the tests by simply hanging a suitable weight or a couple of buddies on their guide plate, itīs not rocket science.
Or hook the rope up to your car and see if the rope "never" slips past.
I have no intention of contacting BD about their guide plate, it is their product and for them to give recommendations for use and the limitations. If they would care to put in writing that the rope will never slip then it looks like I have 3 warranty claims to make as the three I possess DO slip. That said, I have no intention of ever using a guide plate anyway (I use a ATC XP and a Grigri)!
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ontheedgeandscaredtodeath
Trad climber
San Francisco, Ca
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Jun 16, 2010 - 03:05pm PT
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I bought a Reverso cause I thought it looked cool and I liked the color. I don't guide and know how to get myself up a rope if need be. I keep my brake hand on the rope.
Based on the foregoing, is there anything I need to worry about?
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