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Rock!...oopsie.
Trad climber
pitch above you
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Aug 19, 2007 - 10:17am PT
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I think the return of the pulley deserves a thread of it's own, or did I miss it?
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Thom
Trad climber
South Orange County, CA
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Aug 19, 2007 - 04:24pm PT
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You are correct Pete, about the Metolius spreader bar. I have a double and have slept single on it a few times; it absolutely required cinching the center divider up to keep the bed off the bar. I'm 5'9" and 160 lb and that bar lands right in the small of my back and can be felt even through my comfy Thermarest.
Being forced to sleep to one side or the other of the ledge is a balancing act at times. So far, no problems but I'm constantly paranoid of flipping the thing in the middle of the night.
Cheers
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Shack
Big Wall climber
Reno NV
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Aug 19, 2007 - 07:53pm PT
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FISH of course....DUH!
Do you guys take sleeping pads/thermarests even in warm conditions?
My FISH ledges are way comfy even without any pads.
I sleep like a drunk baby.
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Mungeclimber
Trad climber
sorry, just posting out loud.
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Aug 20, 2007 - 01:29am PT
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as to pads on hot days, I don't think i would normally but attempting Freak Show last year I ended up getting chilly and the padded section, when I was on it, was when I was sleeping good. fwiw...
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Tom
Big Wall climber
San Luis Obispo CA
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Aug 20, 2007 - 04:05am PT
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Aluminum is such a hideous material for portaledge tubing, I can't believe some companies still use it. A big reason the FISH ledge weighs less is because the tubing weighs less; and yet, like magic, it's stronger and more resilient than aluminum.
On TR two years ago, a teeny bit of snow-and-wind action (mid JUNE) batted a Metolious ledge around enough to put a ding near the middle of the side tube where it hit the rock. Subsequent extreme loading (i.e., getting in and out of the ledge) caused the tube to bend, threatening to kink completely. The only thing that saved me was wrapping empty beer cans and duct-tape around the tube to splint it.
And the spreader bar? The Metolious ledge I used was only a single, but the spreader bar could still be felt, at times. If I laid perfectly flat on my back, splayed out like a man in a quicksand pit, the bed fabric stayed off the bar. Otherwise, I'd feel it. If I rolled onto my side, it'd hit me. If I sat up, I'd have to move to avoid it.
The fish double can take two people standing on it, digging into a piglet full of pins and huge cams, and not require a spreader bar. The shark-fin straps can be used if the climbers are particularly heavy.
And don't even think of flagging a ledge with aluminum tubes, unless the route is overhanging. The upper corner of the ledge (the one not clipped to the rope) will catch on all manner of TINY roofs, and the ledge will deform into a twisted parallelogram, putting enormous stress at the corners. I can only imagine what sort of other rock features a spreader bar would like to grab.
The FISH ledge can deform and twist into a pretzel, and then spring back, undamaged.
If you intend to belay from your ledge, hauling it flagged above the haul bag is very convenient.
The FISH fly comes with a long tent pole, that increases the interior volume tremendously. Even better, you can run a strap of webbing down the pole, tape a hook to the top, and create a Lovetron/Tequila Straw cheater stick.
All of which means: buy the FISH ledge.
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Holdplease2
Big Wall climber
Yosemite area
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Aug 20, 2007 - 09:35am PT
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You can't really flag a Metolius ledge, or one that relies on a spreader bar. As the ledge torques a bit, or as the spreader bar even "brushes" against the rock, it will fall out of the ledge.
This then allows it to hang down and its tether will wrap around the pigs, eventually causing the pigs to spin.
This is only your biggest problem until the whole ledge falls apart because the poles of the ledge fall out of the "cupped" corner joints without the spreader bar in place.
NOT that I'd know, or anything...
I have never felt the spreader bar on the Metolius ledge, but that's probably because I only weigh 115...OK 120...nevermind. 130, but it still counts. ;)
-Kate.
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Ain't no flatlander
climber
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Aug 20, 2007 - 10:29am PT
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Fish is okay...for short people. Anyone over 5'9" or so will be happier in a manly-sized ledge. If you tension the Metolius well, it's still the best choice.
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deuce4
Big Wall climber
the Southwest
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Aug 20, 2007 - 10:48am PT
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Ah, the battle of Aluminum over Steel, always an interesting one from the engineering perspective.
Both steel and aluminum have advantages and disandvantages. The factors to look at:
--Strength: 6061-T6 aluminum has a slightly better strength to weight ratio than CroMo steel, so a given ledge design based on bending strength will be slightly lighter with aluminum over steel (but only about 5%, not really significant in terms of overall portaledge weight).
--Crack propagation: Aluminum is better; over time, as a ledge gets bashed around, steel will be more vulnerable to micro fractures that could ultimately cause a weak spot and ultimate failure.
--Stiffness: Perhaps the main factor in designing a frame for a portaledge. Based on engineering studies, I found that 6061-T6 aluminum is stiffer than Cro-Mo steel based on real-world tubing diameter and wall thickness designs. (I would suggest that one reason why Fish ledges appear to be stiffer than a Metolius is their relative sizes: The Fish model is compact, so it doesn't flex as much, but if it were as large as the Metolius, the steel frame would flex significantly more.)
--Buckling: A factor of tubing diameter and wall thickness. A 0.058" thick wall 6061-T6 tube has about the same buckling resistance as the Fish CroMo ledge tubing design. However, Tom may have a point in terms of what happens when a significant dent is created in the aluminum tube, as steel may have more resistance to getting dented in the first place due to its hardness.
--Size: Steel is far more compact for packing.
I suppose I had a preference for aluminum for the A5 ledges because I had been in a few lightning storms on walls, and aluminum alloy is not a good electrical conductor, but steel is. Though in reality, no one has ever been struck by lightning on a ledge, as far as I know, and besides, maybe the ledge would act as a Faraday cage.
I was also concerned about rust (in terms of the fitting of the joints), but this also doesn't seem to be a big problem with Fish ledges, by all accounts. For me as a designer, it really came down to the superior stiffness of aluminum (a factor of the larger diameter yet lighter tubing).
This battle has raged on in the bicycling world as well:
http://www.epinions.com/content_1285660804
http://sheldonbrown.com/frame-materials.html
http://www.waltworks.com/dev/philosophy/steel.php
and many others you will find on google...
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YetAnotherDave
Trad climber
Vancouver, BC
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Aug 20, 2007 - 12:54pm PT
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Has anyone else tested using a diagonal strap to keep a metolius ledge from sagging, to prevent the scenario Kate described? I've done a little testing in a fully free-hanging situation, and it seemed to prevent deformation that could let the spreader fall out, but I haven't hauled it anywhere that it could knock against the wall.
Test was with a double bombshelter, strap was an adjustable daisy between two other pieces of tied webbing. I'd also tensioned the bejeezus out of the ledge :)
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Tom
Big Wall climber
San Luis Obispo CA
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Aug 21, 2007 - 01:16am PT
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Deuce4,
I have to take exception to your statement regarding this:
Steel conducts electricity better than aluminum? Then why is it, the PG&E-type power companies often use steel cable to support aluminum electrical cables between poles? I'm too lazy to look this one up, but, as NostraThomas, I predict that any handbook will show aluminum to be the better conductor.
The great tragedy/failure of aluminum is its low yield strength - lack of springiness - which rears its ugly head when an unanticipated load causes minor damage. Basically, aluminum is easy to dent, and it won't spring back. Minor damage like that, in a ledge tube, can, and will, become worse.
By contrast, the cro-moly is almost impossible to damage. It just springs back. The only thing more resilient would be titanium alloy, like they use for those eyeglass frames you can tie into knots. My ledge has carbon fiber tubes, which are incredibly strong (and light), but I would still bet that the FISH ledge would win in an Ultimate Flagging/Destroy the Ledge contest.
PTPP's FISH double ledge is the only test-case I know of, but he's been up, what, 50 El Cap walls with that thing? Russ sent him a replacement bed and new straps, but the frame is 100% original. And believe me, I've seen, and done, hardcore tweaking of that Crab-O-Ledge, pulling past roofs, where it almost twisted 180 degrees on itself, popped the roof, and sprang back, like magic, and ready for use. The only damage to PTPP's ledge frame is some slight flaring at the ends of the tubes, which actually makes the ledge easier to assemble. This is what the Experts call an evolving, adaptive system, or something like that.
The FISH ledge uses aluminum corners with lugs that fit into the tubes. As the tubing flares, and the lugs wear down, it becomes easier - not harder - to assemble the ledge. Is that true with the other designs?
Oh, and the cro-moly is very rust-resistant, in case someone wants to claim corrosion is an issue. The light surface rust on PTPP's ledge frame is nothing more than a decorative patina. My guess is he's had it for almost fifteen years, although that may be an understatement. Basically, corrosion of the FISH cro-moly frame is not an issue.
And for a point of comparison, when was the last time anyone saw an aluminum piton? I bootied a big, fixed, aluminum Chouinard bong last year (ahhh, patience) but that's not the point. The point is, Salathe's genius was to use good, hard, strong steel for pins that need to undergo repeated, high-stress loading, again and again and again.
Russ's genius was that he extrapolated from the Salathe/Chouindard piton to the portaledge tube, and you know what? It works. A big part of Russ's genius was in selecting thin-wall, light cro-moly tubing, but knowing it was strong enough for its purpose. His design is very close to perfect, in terms of strength-to-weight ratio.
My calculator shows that increasing the FISH ledge from 6.5 to 7.5 feet would only add 6 ounces of frame weight. Maybe it's time to petition Russ to increase the size of his ledge, because climbers are demanding a higher level of luxury, up there, on the Wall.
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'Pass the Pitons' Pete
Big Wall climber
like Oakville, Ontario, Canada, eh?
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Aug 21, 2007 - 02:56pm PT
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Mr. Dusseldorf,
I am writing to ask you what you mix with your aluminium to render it non-conductive to electricity? My own experimentation with mixing rubber and aluminium has proved unsuccessful.
I would think the determining factor in ledge stiffness would be less about the material from which the tubes are made [steel vs. aluminum, both of which are pretty darn stiff] and more about the design of the corners. Thoughts?
If it were possible to destroy a FISH ledge, I would have done so long ago. The most I have done is very slightly bent one of the tubes, not enough to worry about trying to straighten. Tom's right about the ends of the tubes being slightly dinged, but this makes the ledge easier to assemble.
One of the reasons I flag the Crab-O-Ledge is because it is hard to set up and take down. This isn't because there is a problem with the FISH design, but rather because the shoe repairman sewed the Crab-O-Flag onto the bottom of the ledge bed too tightly.
I am 5'9" and find the FISH double plenty roomy. I don't know if Russ cuts his own tubes, but perhaps if you are tall he could make you a bigger model?
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paganmonkeyboy
Trad climber
the blighted lands of hatu
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Aug 21, 2007 - 04:13pm PT
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shameless fish promo bump...brand new, present to myself after the new shoulder, can't wait to get it in the air...
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Lambone
Ice climber
Ashland, Or
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Aug 21, 2007 - 04:32pm PT
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everybody seems to be forgetting that it takes a min of 6 months to get a Fish ledge...
I used a buddies on the Shield and have to say that I liked it.
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Moof
Trad climber
A cube at my soul sucking job in Oregon
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Aug 21, 2007 - 04:45pm PT
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6 months? Hell, I just bought Russ a beer with paypal, and voila, I had mine in a mere 180 days!
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Nefarius
Big Wall climber
Fresno, CA
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Aug 21, 2007 - 05:39pm PT
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The Metolius spreader bar sucks. You can feel it, right down the center of your back. I would assume the BD is the same.
Someone above mentioned flagging the ledge... Not going to happen with the Metolius (or BD now), as the spreader bars will pop out and get tangles in everything. Not to mention, your ledge will eventually fall apart without the spreader bar.
And speaking of that spreader bar... You better practice putting hte ledge together on the ground, as well as read the instructions on how to do it. It will save you TONS of pain on the wall when you are flailing, for about an hour, trying to put the thing together. Seriously. Read and practice before you take off. There's an easy way to do it and a painful way.
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'Pass the Pitons' Pete
Big Wall climber
like Oakville, Ontario, Canada, eh?
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Aug 21, 2007 - 05:50pm PT
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What's the loop in the bottom of each strap, right above the ledge? Is that another place you can fine tune the adjustment?
See how each of the six suspension straps has a mini 3-point daisy chain clip point? Very handy - fundamental, really, for big wall camping. I have a whole system every night, what I clip to each place. I would be lost without the clip-in points on each strap. Not every ledge has those, you know. The Cliff Cabana I reviewed didn't have the feature. The other main daisy that FISH includes and what you see hanging down is somewhat handy.
One problem I noted with the Cliff Cabana is that the adjustment straps had only 22" adjustability, which is totally insufficient in all but the most perfect of hangs. Often you have your pig and ledge off the same power point, and you have to hang the ledge asymmetrically, with the straps close to the pig short, and the other end way long. Very handy with FISH, impossible with Cliff Cabana.
Cheers,
Dr. Piton
Big Wall Parvenu
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Holdplease2
Big Wall climber
Yosemite area
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Aug 21, 2007 - 05:58pm PT
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OH I SECOND HOW MUCH THE LIMITED ADJUSTABILITY OF THE BD SUCKS ASSSSSSSS!
I got stuck bivied in a corner on two occasions, and I couldn't get the straps adjusted enough to get the powerpoint close to the corner (even on a sling) and not have the ledge tilted at such an angle as to be nearly dumping me out.
Also, gone are the days of placing the short side of the ledge against the wall. Impossible with either of the new BD ledges. Quite possible with the FISH and Metolius.
-Kate.
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'Pass the Pitons' Pete
Big Wall climber
like Oakville, Ontario, Canada, eh?
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Aug 21, 2007 - 06:01pm PT
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Ledges with insufficient adjustability in all six straps work fine in theory.
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Jaybro
Social climber
The West
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Aug 21, 2007 - 06:03pm PT
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The pond is stocked, forget that other junk, go with the fish™.
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