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tradmanclimbs
Ice climber
Pomfert VT
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Topic Author's Original Post - Nov 22, 2017 - 03:46pm PT
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Ice season is starting again here in the NE. For awhile i had 8 screamers on my rack. the last few seasons it was 4. contemplating saveing the weight and bulk and not putting them on the rack???
The few anecdotal stories that I know of the screw was likly bomber anyways. screw in good ice = bomber. Screw in crap ice = probobly worthless? Will a screamer turn a total crap plecement into a life saver? Any real tests that prove that screamers actually reduce the load on the protection point?
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Ezra Ellis
Trad climber
North wet, and Da souf
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Nov 22, 2017 - 03:54pm PT
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Maybe just Cary one or two for somewhat marginal placements??
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tradmanclimbs
Ice climber
Pomfert VT
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Topic Author's Reply - Nov 22, 2017 - 04:07pm PT
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kind of what I was thinking. good screw no worries. Air pockets, candles, detached crap, slush, stupid thin ice with half the screw sticking out its better to keep a cool head and don't fall........
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madbolter1
Big Wall climber
Denver, CO
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Nov 22, 2017 - 04:08pm PT
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We've done many drop-tests over the years, using a range of cable-thickness with known breaking strength to simulate placements breaking. In our experience, screamers do little if any good. Any fall/placement combination you'd hope a screamer to help you with is a combination that will almost certainly fully-extend the screamer and pull/snap the placement anyway. And the so-called "scream-aid" version is much worse. You can activate one of those by just bouncing on it with body-weight. In drop-tests, they instantly fully-extended, meaning that the "shock absorber" is gone almost instantly.
As a result of what we learned, we developed our own versions that activate at 1000 pounds and will extend up to six feet before full-extension. We did several drop-tests with these.
The most spectacular one was off of an abandoned railway bridge made of steel girders. We drilled a bolt into a boulder that weighed about 250 pounds. We rigged a rope to set up a 1/1 fall-factor and dropped the boulder over the side for a free fall of about fifty feet. You can imagine the forces generated by such a fall! We had one of our screamers rigged onto a set of cables, so that we could observe what broke. Surprisingly the first cable in the mix, a 3/32 stainless (like a #1 or #2 copperhead) held the fall, and the screamer about 1/4 activated (ripping about 1/4 of the way out) to bring this boulder to a stop.
Long and short: Our experience is that store-bought screamers just don't work for all but a few edge-cases, and you really need to create something custom to actually work "as advertised."
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Jon Beck
Trad climber
Oceanside
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Nov 22, 2017 - 04:16pm PT
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In drop-tests, they instantly fully-extended, meaning that the "shock absorber" is gone almost instantly.
Regardless of the type of screamer you use, every time a stitch pops energy is dissipated. If the screamer fully extends the final force will still always be less than a screamerless fall.
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wilbeer
Mountain climber
Terence Wilson greeneck alleghenys,ny,
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Nov 22, 2017 - 04:47pm PT
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I agree,had a fall /slide /ride years ago on the Gothics,watched a couple of stitches rip and it slowed me enough to gain control,when I came to a stop ,the screw popped.
Skeered the living sh#t out of me.
Remember it like it was yesterday.
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Roger Brown
climber
Oceano, California
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Nov 22, 2017 - 05:12pm PT
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At work, tooled up, wearing a full body harness I took a fall into open space. The screamer built into the lanyard only extended about 18 inches out of a possible 6 feet. It was a really soft catch. At work tooled up I weighted around 225 pounds.
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'Pass the Pitons' Pete
Big Wall climber
like Ontario, Canada, eh?
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Nov 22, 2017 - 06:19pm PT
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They sure work for me! Great soft catches, the gear doesn't pull.
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madbolter1
Big Wall climber
Denver, CO
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Nov 22, 2017 - 06:46pm PT
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It's the classic line, "Your mileage may vary."
Careful out there!
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