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epoch
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Nov 19, 2008, 12:48 PM
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I think the one in the aforementioned picture that inspired this test is one of the 'hard' plastic ones. Not the cloudy soft type.
Any chance you'd be able to recreate it with the other type of Nalgene? With and without water inside?
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rockforlife
Nov 19, 2008, 12:50 PM
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Not to ruin the fun but would it be posible to use one of the "real " ones, i have noticed the kind (White) you used bend a lot easer.
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jdefazio
Nov 19, 2008, 12:54 PM
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Nice. 
Seriously though...I'd imagine a better result with the transparent type. I think those white ones are closer in properties to a PTFE.
edited to add: D'OH! Beat to the punch twice! Like Epoch suggests - completely full of water is also very different (incompressible), but very unlikely. If you are SOL enough to use this as a chock you've probably been out long enough to drink it all by then. ;-/
(This post was edited by jdefazio on Nov 19, 2008, 12:59 PM)
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sed
Nov 19, 2008, 12:54 PM
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Now that's science!
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GeneralZon
Nov 19, 2008, 12:55 PM
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This one.
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adatesman
Nov 19, 2008, 12:56 PM
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h4lf_rope
Nov 19, 2008, 1:14 PM
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Lexan is polycarb.
I believe that the new bottles are LDPE.
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shockabuku
Nov 19, 2008, 1:15 PM
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adatesman wrote: Yeah, the one in the original pic is lexan, not polycarbonate and much sturdier. I'll see if I can go scrounge up a lexan one for comparison.
I think lexan is polycarbonate. I think you meant polyethylene. Anyway, I have a whole bunch of the lexan ones if you can't come up with any others. Full vs. empty would be interesting.
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angry
Nov 19, 2008, 1:21 PM
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So yes, I took that picture. It's my bottle. I still have it in fact.
So the bottle was in a constriction tight enough that it couldn't pull through without deforming.
One .75 was totally tipped out (should have been a 1 or even 2), the other was good except that it was placed in a flake. The Nalgene was pushing on the flake thus keeping the .75 in. It's more complex than what a wedged nalgene can hold.
In an ideal world, I would have had a 2 camalot and 4 camalot for that anchor. I had placed them on the previous pitch so this is what I came up with. Fortunately, it was the easiest pitch of the route (Astroman) and my partner was very unlikely to fall.
Why all the red X's, I'm really interested in this one.
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adatesman
Nov 19, 2008, 1:24 PM
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angry
Nov 19, 2008, 1:29 PM
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A couple other things.
First off, the pics are now showing up.
It looks like you've clove hitched that bottle. Mine had a loop running over the top. I think the clove could crush the bottle in a squeezing motion where the plain ol' loop just pushes down.
Also, it was the grey lexan, which IME, is even tougher than the colored lexan.
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adatesman
Nov 19, 2008, 2:43 PM
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dingus
Nov 19, 2008, 3:28 PM
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I'd be curious to compare 'empty vs full' failure mode. I think a full jug would make it considerably stronger?
DMT
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kennoyce
Nov 19, 2008, 3:37 PM
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I highly doubt that full would make any difference at all since the lids on nalgenes are very weak. As soon as it started to deform, the lid would just pop off, and there would go your water. Thats my guess anyway.
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basilisk
Nov 20, 2008, 1:33 PM
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Well hell, if we're gonna do a full one, then I'd like to suggest a full one that's been frozen as well.
Come to think of it, a whole series of ice chockstones could be really interesting. Could do all sorts of things there: shape, volume, density, general quality, etc!
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joeforte
Nov 20, 2008, 2:45 PM
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jdefazio wrote: Like Epoch suggests - completely full of water is also very different (incompressible), but very unlikely. If you are SOL enough to use this as a chock you've probably been out long enough to drink it all by then. ;-/
I think a near-full bottle would be much stronger. I've you've been out long enough to drink it all, than you could most likely piss long enough to fill it back up! A few other random items could displace some water (umm, urine) as well. I want to see the test done with a full, old-school nalgene! I think just a little airspace could help the bottle "give" without bursting. You don't want so much airspace that it can collapse, just a little. I remember a similar physics experiment, and a little airspace made a huge difference in the strength of the container.
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evanwish
Nov 20, 2008, 7:57 PM
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basilisk wrote: Well hell, if we're gonna do a full one, then I'd like to suggest a full one that's been frozen as well. Come to think of it, a whole series of ice chockstones could be really interesting. Could do all sorts of things there: shape, volume, density, general quality, etc!
at that rate, might as well just buy another #4 cam
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basilisk
Nov 20, 2008, 9:52 PM
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evanwish wrote: basilisk wrote: Well hell, if we're gonna do a full one, then I'd like to suggest a full one that's been frozen as well. Come to think of it, a whole series of ice chockstones could be really interesting. Could do all sorts of things there: shape, volume, density, general quality, etc! at that rate, might as well just buy another #4 cam
Cams are expensive. Ice can be free
Think about it, it the days of old climbers carried rocks and machined nuts to use as chocks. Now we could be carrying chucks of ice in our pockets. It's genius I tell you!
But no really, I think ice testing would be really interesting. When I'm out ice climbing I find myself slinging and rapping off ice pillars, not unlike the one below. It'd be interesting to have some idea of the actual strength ice has. I've been terrified of these things giving out more than a few times.
P.S. Sorry for hijacking the thread
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jeremy11
Nov 21, 2008, 10:48 AM
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300 lbs - enough to rap off of! 
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coolcat83
Nov 21, 2008, 11:03 AM
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i was thinking the same thing. if the choice is sit and die or maybe fall and die i'll take maybe. and i bet the lexan one would hold up better.
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ski.ninja
Dec 3, 2008, 8:01 PM
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Just as a side note, it might be worth comparing the 'old style' Outdoor brand nalgene's with BPA (removed due to health concerns) and the new Everyday brand bottles which are made of something called Tritan. You may recall some nalgene bottles disappearing from MEC and REI last summer. The new non-BPA bottles made of Tritan have the word 'other' printed next to the recycling logo.
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adatesman
Dec 3, 2008, 8:09 PM
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no_email_entered
Feb 11, 2009, 9:24 AM
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where are we at? theres a deal on nalgenes on rei and I can get a whole set for a lot less than bd hexes...
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adatesman
Feb 11, 2009, 9:43 AM
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jrathfon
Mar 2, 2009, 10:19 AM
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ski.ninja wrote: Just as a side note, it might be worth comparing the 'old style' Outdoor brand nalgene's with BPA (removed due to health concerns) and the new Everyday brand bottles which are made of something called Tritan. You may recall some nalgene bottles disappearing from MEC and REI last summer. The new non-BPA bottles made of Tritan have the word 'other' printed next to the recycling logo.
So I'm finishing up my PhD in polymer science. The original opaque nalgenes are HDPE (high-density polyethylene) the "old" translucent and/or colored hard nalgenes are lexan, which is a form of polycarbonate. One of the monomers as well as the plasticizer (like a solvent, makes the plastic more pliable (softer)) in Lexan is bis-phenol A (BPA). The BPA free bottles are made of Tritan, which is a polyester. Tritan is similar in structure to Lexan except that Tritan has ester groups (OC=O) and Lexan has carbonate groups (C=O). (a few other differences, but not worth explaining)
The main point is the 3 plastics have VERY different materials properties HDPE is very tough, yet does not have a high modulus (strength). Lexan has a high modulus, but is very brittle (not tough). Tritan is about half-way between and has been tuned to be strong and tough (~ 1/2 as strong as Lexan). There was a great deal of thought put into the development of Tritan (the inventor gave a colloquium here recently), so Tritan is more resistant to a number of chemicals, will not leach as much or retain flavors, and is capable of being used carbonated beverages. It however does degrade readily in UV light.
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