prusik backup for toprope solo

Ok so for top rop soloing lets say you want to backup your primary top rop solo device, which for me i'm looking at using a petzl ascension because i already own one and do not own a minitrac, and petzl approves of this use. Anyway you wanna back it up with a different type of device, (both minitrac and ascension ect use a toothed cam) couldn't one put a prusik above the ascender and just have the ascender push the prusik up? I set this system up at my house and "climbed" the porch and found the drag to be acceptable to me (simulated rope drag on lead lol)

here is a pic:

I used a 5mm prusik, but would want a 6mm for a real run I later experimented with a 6mm and found it slid just fine when tight enough to lock up. I was also thinking adding a spacer between the prusik and ascension might be wise.

anyway i've searched around and didn't see anything about this on MP or google. Why would this be unsafe?

and yes i'm gonna die

I've done a bit of research on this as well. Basically I think general consensus is that there is enough chance of the prusik not catching that no one will trust them. I recall hearing that once upon a time 40 or 50 years ago using a prusik backup was standard but as soon as everyone realized there was quite a risk people moved on to other systems.

Someone with more info please correct me if I'm wrong.

In a community notorious for dirtbagging and often being as cheap as possible there is usually a safety issue when no one is using the super inexpensive seemingly obvious solution

A few maybes:

With the prussik above the device;

I can see it being possible to suck the prussic into the ascender.
If the knot slides that easily, it may not be tight enough.

I would consider putting it under (???) And, dynamic cord seems a safer bet.

Just a start for your discussion! ;-)

I also use the Petzl setup but I would say there's really no need to backup the ascender with a prussik because you have the biner clipped through the ascender. And even if it were to pop off you would still have the second fixed strand of climbing rope (I assume not shown in your picture) with a secondary device on it, right? That's your backup in the Petzl system. Primary Ascension clipped into primary strand with locking biner into belay loop and secondary device on second strand (I used a microscender on a dog bone) clipped with locking biner into belay loop. Slides easy enough to forget about once you're 10-15 feet off the deck.

And, is this prussik "risk" operator error (not pulled tight, not enough wraps, wrong material choice) or real? If SAR uses it, what's going on here?

I wouldn't TR solo on that setup. Prussiks don't reliably catch when dynamically loaded.

The only way I would consider that setup acceptable is if you had a secondary line with backup knots tied every 10-20 feet and clipped into them with a locker.

If you put the prusik under the ascendor than nothing pushes it up I experimented with using a pulley to mind the prussik and it worked but seemed overly complicated. additionally in the event that the ascension strips the sheath off the rope you would need the prusik above the ascension (thats why i was thinking of like a pvc pipe spacer or somthing)

As far as a second line I'm aware of that practice, but also find articles detailing double microtrac setups on 1 line, but the safety of that seems debatable (and i have 0 microtracs). Also for a 2 line system you either need to run another ascension or microtrac (which i thought couldn't handle a real shock load like if your primary failed) so that would leave you trusing a grigri type device and having to take the time to pull slack out of the grigri, or tying knots in the rope which seems cumbersome

also I can't see the 6mm cord jamming the device, a spacer might help with this as well, and in the event it did jam I would just have to rap down (shouldn't be doing this if you can't escape anyway)

I'm totally open to the idea that this is probably not be a good idea, just talkin it out. thanks

You won't generate enough force to strip the sheath on your rope if the ascender is attached directly to your belay loop as per Petzl because there is no fall distance before it engages.

Just to try and help you out having done this a bit, the problem I see with having a prussik on there above your ascender is that the minute the route you're on requires you to move your body one way or the other (rotate hips, heel hook... whatever) the prussik is going to cause the rope to bend a little and not want to slide through the ascender. You really need the second strand of the rope to do this safely. Two devices on one rope isn't very redundant, especially where the strand is fixed and you can't monitor what its doing above.

You also won't shock load your second device because it is only trailing the primary by 6 inches - the length of the dogbone. Plus, you are not really "falling" as you would on lead since (if the system is sliding properly) you are simply weighting the device when you come off. Since both strands are dynamic, if enough rope is out (50-100 foot crag) there is nothing to it - very gentle.

If you can't afford a second device (microscender etc.) then as suggested tie back up loops in the second strand every few feet and clip in to your belay loop with a locker.

Also having done my fair share of TR solo, i would not use this system. First the prussik will probably need tending if you put more wraps in, which you will probably need to catch well. Second you only have one rope. I would use 2 ropes, its annoying, but as mentioned you can't see whats going on above you. Is your rope getting cut on some stupid little flake or edge? You can't see and although the risk is small, the consequences are massive. If you use a chest harness to hold your primary device high, then both the primary and secondary are always close and the fall distance is really just the rotation of your lockers, even on a static rope, not a big deal.

For my set up, i use 2 9.7mm bluewater dynamic ropes. my primary device is the climbtec roll-n-lock with a chest harness. For my secondary I use a grigri 1. I tie knots in both lines below me as I go. You can weight the rope for the grigri and have it self feed, I do it some times, you just have a lot of weight pulling on your harness that way. I'm okay with that, because to me TR solo is practice. So stopping to tie knots with one hand and pulling weight with my harness just add to the challenge.

that's fair i hadn't really thought about how it could wear the rope like jugging a line, I had been thinking "I only need one rope to lead why 2 to TR" but yeah i could see it getting cut or something crazy.

If you know your going to have a ledge or something that will wear on the line, try and pad it with an old towel, or get a rope protector. I try to be very careful with my TR soloing. If anything goes wrong, you are alone, so i feel that i should take extra steps to control risk. Its all about what you feel comfortable with, I have met guys that TR solo with a single device on a single static rope, and that works for them, but i would not feel comfortable with it. Be safe have fun, and ask questions, a lot of people on MP TR solo.

Zacks,

I just happened to be able to get out yesterday on my solo rig, so I hung out mid-route and took a pic for you - easier than describing. As you can see the second device sits only a little higher than the primary, and in this picture it's not weighted - just backing me up. The lockers I use are ovals because they are far less likely to work themselves into a position where they might be cross loaded. Also you might note I have two belay loops (BD Big Gun harness) which I use specifically for top rope soloing to help keep the two devices from binding on one another when weighted. What isn't shown are the two 1 pound fitness weights I clove into each line near the ground. This is just enough weight on the lines to keep the device moving, but you could also clip your pack, or a water bottle, or whatever.

If you're gonna do this make sure you also practice how to unweight both devices mid-route and safely transition over to rapelling, since you'll need to do that if you can't get to the anchor to clip it. If you can get to your anchor, a PAS or sling is nice to clip in and switching is easy. If not, standing in a clove hitch works well for me. Hope that helps. Climb safe!

Matthew - your primary device is that red micro-/Recu-ascender on top, right? It trails behind you as you climb due to the draw etc. Looks like every fall is upwards of 4 feet. No thanks!

nah that looks like a petzl shunt and that should be his backup, the ascension clipped directly to the belay loop is the primary. I think he just pushed the backup up the rope for the pic.

I understand how to rig the system ect and how to escape it. I bought the ascender a while back when I was doing vertical caving with a buddy and he bought the lefty one lol (we where cheap!) I had just been told to avoid using 2 devices of the same style for TRS but i guess with 2 ropes it would be ok. I even recall the manual for my petzl ascender (i thought it was the manual maybe I read it somewhere else) which is a little older now to say you should back up with a prusik when jugging in case both ascender cams popped. I can't find anything like that anymore so...

Anyway I was buying a cam off a guy on mp and he was like hey do you wanna save on shipping and buy a micro trac. So I was like whelp the universe is sure telling me something here and said yeah gimme that too lol.

arborists use a similiar system for single rope work, try using really thick (8-9mm) cord for the prusik, it should make things a little smoother and completely eliminate any risk of it getting caught in the device.
Edit: I assume you are going to bring a grigri with you for the decent?

Gunkiemike wrote:Looks like every fall is upwards of 4 feet. No thanks!

Yeah I highly recommend stringing your primary device up by your chest.

Zacks, now that you have the micro trax you're all set - hang that sucker down as your back up and fix the ascender up at your chest. I use a handleless ascender and a kong duck as a back up in this fashion, couldn't be happier.

The arborist comparision is not entirely accurate, in that system you have a pulley right underneath the prussik that tends it and makes it easy to pull slack through.

Don't expect a prussik to catch once it's sliding, in about 10 feet or so you can melt right through the whole chord.

Your initial setup of ascender+prussik is what I've used consistently for five years in a variety of settings (slab, ice, offwidth, chimney, ropes course). Here are a few tweaks that have helped:

- Rig a chest harness out of a four-foot sling and clip it to the ascender. This keeps the device upright, feeding smoothly and minimizes slack in the system.

- Sterling Hollowblock for the prussik. With three wraps on a 9.8 rope, it slides and grips on cue.

- Weight the rope. Chacos or a liter of water are just right for me.

- Pad the edge at the anchor.

- For long routes, tying off the rope at intermediate anchors helps mitigate initial rope stretch if you've got a cruxy start.

- Bring extra biners, slings, a healthy sense of self-sufficiency, etc.

Lots of great times of reflection to be had TR soloing, plus lots of mileage in a short time period. Have safe out there, be fun.

an untended prussic may not catch a fall ... and itll be untended if you uses it to TR solo, and somewhat loose to move up without catching

it needs to be fairly snug and constantly minded with a hand to be "reliable"

We realized that these 14-15 years olds were ascending the cave route via a single fixed line. For protection they used a prusik knot attached to their belay loop. As I mentioned there were 2 people climbing the route as we approached. That means they had 2 people on the rope at the same time with about 15 feet of space between them. There was a boy near the top and a girl starting the route as we approached. We sat down and quietly began talking about what was going on.

The girl had difficultly climbing the cave route and was breathing hard as she approached the lip about 20 feet up. As my friend and I contemplated how to approach the adult our worse fears came true. The girl fell at the lip the full 20 feet without the prusik knot catching (who’s surprised?). She screamed as she fell and hit the ground at a 45 or so degree angle, her ankle hitting first.The guide on the ground (there were 2 others up top) stood there doing nothing there as the girl tried to get her breath back. For a moment we waited for him to assess the situation but he just stared at her. We got up and checked the girl for serious injuries and then moved here to the cave where we could elevate her foot. The adult at the base kept saying “that should have held”.

Once the girl was safe we asked the guide why they were using that “system” to ascend the rope. He said it was faster as they had several kids that they needed to get up the climb. We told him that it was unsafe, as we had just seen, and that they should belay these kids up. It’s important to mention that these kids we struggling on the 5.7 cave route before the girls fall and should have been on a tight belay. I asked one of the other kids to run down to the river where the backboard and a pair of crutches were. The kid ran off to get crutches and the guide, to my surprise, proceeded to send more kids up the route. He continued to send kids up the route on the same system that almost injured someone 5 minuets before. My friend and I climbed up the route and at the first pitch told the other adults (the guys in charge we presumed) what happened and they reiterated the “it takes to long to belay” statement. One adult (the leader I think) also said when we mentioned the prusik was not safe said “we’ve been doing that for 20 years” and “it works in mountaineering”.

Upon reaching the anchors of the cave route we saw that they did not even used both hangers for the rope but had the rope clipped of on a bite attached to a hanger via a quick draw. They continued to climb the route despite the fact that one of their climbers was injured. The guides did not seem to care that someone just fallen 20 feet, none of whom went to down to check on her or help hike her down to the canal road. The girl was picked up by a vehicle on the canal road after the adult from below called the park and asked that they open the gate to get someone out. I do not know the extent of her injuries.

mountainproject.com/v/smith…

Matthew Williams 1 wrote:Zacks, I just happened to be able to get out yesterday on my solo rig, so I hung out mid-route and took a pic for you - easier than describing. As you can see the second device sits only a little higher than the primary, and in this picture it's not weighted - just backing me up. The lockers I use are ovals because they are far less likely to work themselves into a position where they might be cross loaded. Also you might note I have two belay loops (BD Big Gun harness) which I use specifically for top rope soloing to help keep the two devices from binding on one another when weighted. What isn't shown are the two 1 pound fitness weights I clove into each line near the ground. This is just enough weight on the lines to keep the device moving, but you could also clip your pack, or a water bottle, or whatever. If you're gonna do this make sure you also practice how to unweight both devices mid-route and safely transition over to rapelling, since you'll need to do that if you can't get to the anchor to clip it. If you can get to your anchor, a PAS or sling is nice to clip in and switching is easy. If not, standing in a clove hitch works well for me. Hope that helps. Climb safe!

2 things

- use a bungee cord around your neck shoulder and clip it through the locker of the extended ascender ... this keeps the ascenders from interfering with each other and keeps it from trailing ... so no increase in fall length (fall factor)

- clip a biner through the bottom hold of you jumar and clip the rope through it ... sometimes the ascender will load sideways (on traversing or funky moves) which can prevent the rope from feeding properly or cause unusual loading in a fall ... the bottom biner keeps the ascender parallel to the rope

;)

Thanks for posting the link to that accident report. Its nice to actually have an account of a prusik not working rather than just the "I imagine that's not safe" speculation.