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rappel device


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new to the sport end of things, i've only been using an ATC for a couple of months now. i do quite a bit of rappelling... not fancy "extreme" rapping, but i like to get on it some and try new stuff. i've noticed this is chewing up my new ATC pretty quick. i've also noticed it gets hotter than i'm used to a rap device getting. inspecting a pretty new (3 months) length of Edelweiss semi-static last night, it seems like the sheath is wearing faster than i'd like. i'm diligent with rope guards, so i have to wonder if excess heat is prematurely aging it...?

 

whatever the case... even if i don't saw through the ATC or melt my line on a long, fast rap, i'm thinking maybe the ATC should be relegated to belaying and rappels-incident-to-climbing, and try something else for dedicated rapping. now that i've been introduced to the world of new fangled fancy sport gear, i'm not going back to the figure 8.

 

so my questions-

 

are my heat concerns with the ATC valid?

anybody used the Sterling ATS, and what do you think?

would another dual-purpose device work better than the ATC? what about the reverso?

what other non-tail-coiling devices should i look at for dedicated rappel?

 

thanks

Edited by bkb0000
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are my heat concerns with the ATC valid?

I've gotten several belay devices too hot to touch, including an ATC. I've yet to get burn lines on my rope. When I'm done with the rappel I get the rope out of the device (if it's hot) so as to not cook the rope. Hard to say if your concerns are valid without being there.

 

 

would another dual-purpose device work better than the ATC? what about the reverso?

I have only been using one for a couple months now but the DMM V-twin is very resistant to heating up. It could be a double edged sword though, if I ever do heat the thing up, it's going to take a while to cool off (stainless steel). As a bonus, you probably won't be able to wear one out for a long long time. Oh yea, if you do get a V-twin, you might want to smooth the edges a little bit with some fine sandpaper. A friend put some fuzz stripes down a new rope because of the rough casting surface on the V-twin.

 

 

what other non-tail-coiling devices should i look at for dedicated rappel?

Ditto what hanman said, a small brake rack.

 

 

 

Chad

 

 

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sterling advertises the ATS as rappellable, but i cant find a single piece of evidence that it's ever been used in a hanging vertical wall rap. im sure it has, but that's apparently not what they had in mind. seems like it'd be good for heat like a figate, but way more versatile and controllable..

 

i've shied away from the racks thus far.. they just don't seem like much fun. maybe i'll see if anyone in my circle has one and try it. are they generally steel or aluminum?

 

i did just watch a video on ATC and heat... according to these guys, and ATC can get up to 200-250 degrees during a long, fast abseil, which is way shy of the 460 degree melting point of nylon... but they were of the opinion that this was still hot enough to damage rope. not melt it off and drop you, but screw up the core somehow. http://www.topclimbing.com/general/episode-9-can-a-rappel-device-burn-through-my-rope/

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I was a caver before I was a climber, and as a result I did a lot of rapping in caves. The lesson learned there was don't use your climbing gear for caving, and vice versa, so I would recommend that you get a dedicated device for your sport rapping from a caving supply outlet, like RaisedByPikas said, or from a rescue supply outfit like Conterra. It'll be a lot beefier than anything you would get from a climbing store. There's a little thing called a hyper-rack, which is pretty small, so not real heavy even for being made of steel, that would suit your rappelling needs just fine. They are generally all steel, although at one time I put aluminum bars on mine, but they wore through so fast from cave grit that I went back to the steel bars.

 

7468.jpg

 

But if you get the v-twin, figure on getting something else for belaying/rappelling for climbing. The newer Reverso or the BD Guide would work well.

 

 

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according to these guys, and ATC can get up to 200-250 degrees during a long, fast abseil

 

I don't usually rap at 30mph, do you?

 

no- probably not. yet. but with this new semi-static, i gotta tell you, i sure have a lot less apprehension about really lettin it rip.

 

either way, the V-twin seems to be the peace of mind i'm looking for. i'll try it for rapping, and keep the ATC for belaying.

 

thanks gentlemen. i'll still be really interested to know if anybody has used the ATS, and what they think of it.

Edited by bkb0000
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either way, the V-twin seems to be the peace of mind i'm looking for. i'll try it for rapping, and keep the ATC for belaying.

 

 

 

US Outdoor Store in downtown has them: http://www.usoutdoorstore.com/outlet/dmm-v-twin-belay-device.html?cvsfa=2293&cvsfe=2&cvsfhu=3134303533

 

 

 

thanks for the lead, man.. i went and grabbed one this afternoon. i took it over to RB and gave it a handful of fairly hard raps... didn't even get warm.

 

mine is virtually flash-free... no sharp edges, no burrs. all the same, the teeth looked a little too aggressive for my liking, so i went ahead and whittled on 'em a little with some 150 grain and smoothed over the points a little. i actually havent looked at my rope yet, but it didn't feel like it was scraping it.

 

my only problem is that it's cast... whats up with that?? maybe i just havent been paying attention, but i don't think i've ever seen cast rope gear. i love the versatility of all this sport gear, but i don't love how flimsy it all seems. 9/16" webbing for anchors? singling with <8mm? uh uh.

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Sobo speaks truth. Bobins are another rap device that you may want to consider, like the Petzl Stop. Also the ability to add or reduce friction is a very nice and safe feature to have. It’s frustrating to have to force feed rope at the top of a 300ft rappel and deal with a runaway train when you reach the bottom or when dealing with a waterfall. I use a stainless mini rack for caving. Again to reiterate, many belay devices are inappropriate for long rappels simply because they are not massive enough to act as a heat sink and quickly become too hot to handle. However racks and bobbins are heavy and unwieldy for short rappels 30m or less so Canyoneering devices usually fit the bill fairly well. For canyoneering I use a Petzl Piranha. They are made of aluminum and are considered a consumable by many especially if you hang out in sandstone canyons. I also have friends who use the ATS and they like it. There is also the Totem which is basically the same as the ATS sans the horns and with a few extra rings, both are a blending of a fifi and a figure eight which isn’t a new idea (Salewa Guide=old) and make for a very useful multi purpose tool.

Edited by Mentat
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my only problem is that it's cast... whats up with that?? maybe i just havent been paying attention, but i don't think i've ever seen cast rope gear.
Where ya been, man? Why does this surprise you? Ever seen a BD Guide? It's cast. Ever seen a figure 8? Also cast. A Sticht plate? Take a guess. I could go on... Cast rope gear is nothing new.

 

i love the versatility of all this sport gear, but i don't love how flimsy it all seems. 9/16" webbing for anchors? singling with <8mm? uh uh.
9/16" tubular has a breaking strength of somewhere around 1,500 to 2,300 lbs. 8mm cord comes in around 2,900 to 3,200 lbs. How much do you weigh, man?

 

I'm in mountain rescue, educated by Rigging for Rescue, and we routinely use 9/16" and 1" tubular webbing and 8mm cord in all our rigging systems. And we're operating with forces much much greater than your rappel kit will ever see. Ya need to know yer math...

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my only problem is that it's cast... whats up with that?? maybe i just havent been paying attention, but i don't think i've ever seen cast rope gear.
Where ya been, man? Why does this surprise you? Ever seen a BD Guide? It's cast. Ever seen a figure 8? Also cast. A Sticht plate? Take a guess. I could go on... Cast rope gear is nothing new.

 

i love the versatility of all this sport gear, but i don't love how flimsy it all seems. 9/16" webbing for anchors? singling with <8mm? uh uh.
9/16" tubular has a breaking strength of somewhere around 1,500 to 2,300 lbs. 8mm cord comes in around 2,900 to 3,200 lbs. How much do you weigh, man?

 

I'm in mountain rescue, educated by Rigging for Rescue, and we routinely use 9/16" and 1" tubular webbing and 8mm cord in all our rigging systems. And we're operating with forces much much greater than your rappel kit will ever see. Ya need to know yer math...

 

negative. you're confusing casting and forging. cast aluminum is extremely weak, and i'll bet a dollar you couldn't find a single piece of load-bearing cast aluminum equipment in modern production. cast metal parts have no structural plasticity. if you take a hammer to a piece of forged steel equipment, so long as you can still get it to link up to your harness/rope/carabiners/whatever, it's not going to break- ask me how i know. whack a piece of cast steel, and it'll likely just crack. ALL of the steel equipment we use in rope access/fall prevention/protection is forged. D-rings, carabiners, screw links, grabs, fig-ates, descenders, hooks, snap-links, anchors, etc, etc. and though i'm not in rescue, i'm willing to bet another dollar that ALL of the aluminum load-bearing equipment you use is forged. i would have made the same bet regarding steel equipment, except that i now happen to own a piece of cast steel equipment. but i bet it's extremely rare.

 

as to my inhibitions regarding sport equipment- my "math" is just fine. i've done my share of bullshit OSHA-required coursework. it's not about break strength- it's about how much sawing/abrasion/heat/chemical exposure/etc it'll take to saw/abrade/melt/dissolve the equipment. bigger is always better, in this regard, and that's why we're not allowed to use sport equipment in RAFP. you'll NEVER see human weight bear on rope skinnier than 11mm, and for lifeline placement, 5/8-1", depending on the material, for a minimum 22kN rating. for webbing, you won't see anything less tha 1.5" tubular, and often 2", and 2" minimum for harnesses and seats.

 

this as my background, i don't think it's irrational for me to be apprehensive. but i'm obviously pushing my fears aside and going with it- i DID use the v-twin, did i not? i've embraced a small pile of aluminum sport equipment, and i even bought a 10,3 climbing rope- ,7 smaller than the smallest rope i've ever used. i'm sure i'll get over it.

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I had some similar reservations coming to climbing from a rope rescue background. Spend some time prusiking up 8mm ropes with 5mm prusiks, and take some leader falls on those tiny camp carabiners and shoe-lace looking dyneema runners, and you'll start to have faith in this crazy looking gear.

 

That said, you should be much more careful about what happens to your climbing gear than you would your commercial equipment. It's plenty strong, but if you damage it there's not a lot of margin left. I replace my 5mm hero loop around twice a year.

 

Have fun and be safe.

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my only problem is that it's cast... whats up with that?? maybe i just havent been paying attention, but i don't think i've ever seen cast rope gear.
Where ya been, man? Why does this surprise you? Ever seen a BD Guide? It's cast. Ever seen a figure 8? Also cast. A Sticht plate? Take a guess. I could go on... Cast rope gear is nothing new.

 

i love the versatility of all this sport gear, but i don't love how flimsy it all seems. 9/16" webbing for anchors? singling with <8mm? uh uh.
9/16" tubular has a breaking strength of somewhere around 1,500 to 2,300 lbs. 8mm cord comes in around 2,900 to 3,200 lbs. How much do you weigh, man?

 

I'm in mountain rescue, educated by Rigging for Rescue, and we routinely use 9/16" and 1" tubular webbing and 8mm cord in all our rigging systems. And we're operating with forces much much greater than your rappel kit will ever see. Ya need to know yer math...

 

as to my inhibitions regarding sport equipment- my "math" is just fine. i've done my share of bullshit OSHA-required coursework. it's not about break strength- it's about how much sawing/abrasion/heat/chemical exposure/etc it'll take to saw/abrade/melt/dissolve the equipment. bigger is always better, in this regard, and that's why we're not allowed to use sport equipment in RAFP. you'll NEVER see human weight bear on rope skinnier than 11mm, and for lifeline placement, 5/8-1", depending on the material, for a minimum 22kN rating. for webbing, you won't see anything less tha 1.5" tubular, and often 2", and 2" minimum for harnesses and seats.

I'm not going to stand here and measure penises with you, bkb, but you're mixing apples and oranges now. You're talking about how you're "not allowed to use sport equipment in RAFP", and that's just fine. You get no argument from me on that. But we're talking about the limitations (and merits) of sport equipment in a CLIMBING/RAPPELLING setting here. You need to throw what you believe about RAFP out the window (when we start talking about climbing) and embrace a new set of principles, because the game is most definitely not the same anymore. As I said, apples and oranges. 9/16" tubular and sub-8mm accessory cords are totally safe for how we employ them and are de rigueur in these applications. Wrap a piece of tubular a couple turns around a rock or a tree trunk and tie it off and you've tripled it's single strand breaking strength (two turns gives 4 strands => 4X single strand strength, then subtract a 1/3 for the knot, ergo 3X single strand strength). Throw a biner or a rap ring in there to attach your rap rope and you've eliminated the sawing action you're worried about. If you're worried about sharp edges on the rock, re-rig to avoid them or pad them with something. It's all in the set-up. Again, I harbor not a single compunction against rapping off a 9/16" tubular anchor. Been doing it for over 25 years now. Just inspect your kit/rig and know what you're doing in the set-up. We're trying to help you in that respect here.

 

this as my background, i don't think it's irrational for me to be apprehensive. but i'm obviously pushing my fears aside and going with it- i DID use the v-twin, did i not? i've embraced a small pile of aluminum sport equipment, and i even bought a 10,3 climbing rope- ,7 smaller than the smallest rope i've ever used. i'm sure i'll get over it.
I believe your fear/apprehension to be misplaced. And just so you know, in mountain resuce we operate pretty religiously along a 10:1 static system safety factor with a base load of 2kN (patient, attendant, and litter/gear), so we're talking about a 20kN minimum system capability. That's only ~10% less than what you operate with, as you note above. We're not that much different, yet we use the stuff you seem to be afraid of all the time, and no one dies. I'm sure you'll get over it, too.
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Ahem....BKB

 

There is nothing wrong with cast aluminum. I'm an engineer in aerospace...at a certain manufacturer of large commercial aircraft. I've seen and used the design manuals. Not going to quote numbers from them, since it's proprietary data. But you should be able to find info in the public domain that supports what I have to say (Mil Handbook 5 is a good place to start).

 

Cast parts are used all over on aircraft - just a wee bit more regulated usage than climbing...m-kay? Something about killing 400 in one shot with a failure, or losing nukes, you know......

 

"cast aluminum is extremely weak" is simply incorrect.

Ditto

"cast metal parts have no structural plasticity"

Again, simply wrong.

 

Now, if you're talking some yahoo melting down pop cans in a steel can with an acetylene torch and pouring the melted residue into a scraped out dirt mold in the back yard, sure, it's weaker than crap.

 

If you're talking about proper casting houses, following strict procedure, well, you show you need to do some research and educate yourself on what the facts are.

 

Is cast as strong (raw yield strength) as machined billet or forgings? Nope. Then again, where castings are used, they don't need to be and the thickness is adjusted accordingly.

 

Like anything, a good engineer will tailor their choices in materials, design and manufacturing process to the desired outcome in terms of operation, strength, weight, cost, bulk, etc.

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Ahem....BKB

 

There is nothing wrong with cast aluminum. I'm an engineer in aerospace...at a certain manufacturer of large commercial aircraft. I've seen and used the design manuals. Not going to quote numbers from them, since it's proprietary data. But you should be able to find info in the public domain that supports what I have to say (Mil Handbook 5 is a good place to start).

 

Cast parts are used all over on aircraft - just a wee bit more regulated usage than climbing...m-kay? Something about killing 400 in one shot with a failure, or losing nukes, you know......

 

"cast aluminum is extremely weak" is simply incorrect.

Ditto

"cast metal parts have no structural plasticity"

Again, simply wrong.

 

Now, if you're talking some yahoo melting down pop cans in a steel can with an acetylene torch and pouring the melted residue into a scraped out dirt mold in the back yard, sure, it's weaker than crap.

 

If you're talking about proper casting houses, following strict procedure, well, you show you need to do some research and educate yourself on what the facts are.

 

Is cast as strong (raw yield strength) as machined billet or forgings? Nope. Then again, where castings are used, they don't need to be and the thickness is adjusted accordingly.

 

Like anything, a good engineer will tailor their choices in materials, design and manufacturing process to the desired outcome in terms of operation, strength, weight, cost, bulk, etc.

'

 

"ahem," as though you're gonna take me back to school or something?

 

how does any of the above contradict anything i've written? in the context of thin-walled, shock-loading, SOLO parts, casting is, in fact, extremely weak, relative to forging. i'm sure you (ambiguous) can engineer beautifully stout cast parts- my father did 10 years at Precision Cast Parts in portland. but in the current, applicable context, cast aluminum is not appropriate. and nobody is going to disagree with that.... so since that isn't your point, what IS your point?

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What is YOUR point? Are you trying to say a reputable climbing company is making a belay device that is dangerously weak? Or has "too aggressive teeth" for your liking? Belay devices don't see much force, cast aluminum is strong enough, those teeth don't damage ropes.

 

You're the one saying you don't trust aluminum "sport gear" and would rather use steel, when everyone else here uses nothing but aluminum equipment, and you're the one saying you think a 10.3 climbing rope is disconcertingly thin, when everyone else here is climbing on ropes in the 9.X range.

 

Take the advice or don't, quit arguing.

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