Inferior weaves of dyneema slings
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There seems to be two types of weaves for dyneema slings |
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I think you are talking 13mm vs 10mm. The blue water titan sort of invents the nylon dyneema bland on the left. The one on right is lighter and reduce bulk but is a higher amount of dyneema in it. |
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Pete Spri wrote:I think you are talking 13mm vs 10mm. The blue water titan sort of invents the nylon dyneema bland on the left. The one on right is lighter and reduce bulk but is a higher amount of dyneema in it. Trade off f durabity vs slimmer and lighter.The example was only demonstrating the weave, i have seen two different 12mm pure dyneema slings have those weaves. examples would be the Petzl St’Anneau and the omega pacific dyneema sling, just checking outdoor gear labs review. |
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Aside from width, I think the nylon is colored and the dyneema is white. The more white, the more abrasion affects it. I think that each brand has different percentages of nylon in it, and the ones with more nylon last longer. |
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Pete Spri wrote: I think that each brand has different percentages of nylon in it, and the ones with more nylon last longer.I agree with this |
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The sling on the left has more nylon (coloured material) in it than dyneema (white material). Whereas the one on the right has way more dyneema in it than nylon. |
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Mark your edits if you add details to old posts after people have replied. So "dyneema" can mean a lot of things, and it's likely theres at least a few different grades of "dyneema" used by different climbing manufacturers. Plus as several people have mentioned, some companies blend in some nylon into their dyneema products, and I would not be surprised if things advertised as simply "dyneema" still have some other materials blended in. (though I don't think there's proof that white=dyneema and color=nylon) Specific evidence of this is the difference between the Petzl "dyneema" slings. The Fin'Anneu and St'Anneu are both "dyneema", and both rated to 22kN. But one is 8mm and the other is 12mm. If they were made of the exact same material, then you might expect the one that's 50% wider to be stronger. So until I see a controlled trial where the same materials are used with each "weave", I don't think there's a lot of evidence that the "weave" is the primary factor in "dyneema" sling durability. I think that the material itself is more likely to the deciding factor. But that's just my guess, I don't think the manufacturers like to release too many of the technical details behind their products. |
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Nathanael wrote:Mark your edits if you add details to old posts after people have replied. Anyways, you showed 2 types of "dyneema" slings, and claimed that one has better wear resistance than the other, even when they are the same nominal width. You want to blame that on the "weave" type. I've never seen evidence of the impact of "weave" type, and it seems like most commenters here haven't either. If you can show convincingly that you're right, and weave is a primary determiner of durability, that'd be pretty cool. The main thing is that you assume that all "dyneema" slings are made of the same material, with inherently the same properties (strength, durability, density, etc). There's no reason to believe this is true. "Dyneema" is just a brand name for Ultra-High Molecular Weight Polyethylene (UHMwPE), and they make everything from fishing line to crane wire. So "dyneema" can mean a lot of things, and it's likely theres at least a few different grades of "dyneema" used by different climbing manufacturers. Plus as several people have mentioned, some companies blend in some nylon into their dyneema products, and I would not be surprised if things advertised as simply "dyneema" still have some other materials blended in. (though I don't think there's proof that white=dyneema and color=nylon) Specific evidence of this is the difference between the Petzl "dyneema" slings. The Fin'Anneu and St'Anneu are both "dyneema", and both rated to 22kN. But one is 8mm and the other is 12mm. If they were made of the exact same material, then you might expect the one that's 50% wider to be stronger. So until I see a controlled trial where the same materials are used with each "weave", I don't think there's a lot of evidence that the "weave" is the primary factor in "dyneema" sling durability. I think that the material itself is more likely to the deciding factor. But that's just my guess, I don't think the manufacturers like to release too many of the technical details behind their products.Just a few points, White doesn't necessarily mean that it's all dyneema, but colored definitely does mean that it is not dyneema. Dyneema can't be dyed and is only available in white and recently black, though the black is not used in any climbing gear that I know of. Generally speaking, in climbing products that claim to be dyneema, yes, the white portions are dyneema and the colored portions are nylon. As far as the strength is concerned, most slings are only bar-tacked to be rated to 22 kN. Most likely on a thicker sling they could add more bar-tacks to get the strength up higher, but they don't do that because more strength just isn't necessary for climbing gear and 22 kN is what is required for UIAA certification. I do agree however that most likely the weave isn't the issue. The more abrasion resistant "weave" obviously has much more nylon in it which is more abrasion resistant. |
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Kennoyce, not challenging your point here that dyneema is not colored, but simply curious as to how you know that? |
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Dan.K wrote:Kennoyce, not challenging your point here that dyneema is not colored, but simply curious as to how you know that?It's pretty well known in the industry that Dyneema cannot hold a dye, and therefore was only available in white, or off-white. A few seconds of googling would have produced answers for you. Black dyneema is a very recent invention. dsm.com/products/dyneema/en… |
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I guess I should have been clearer, I was curious about what kennoyce's job is that would lead him to that information as that's not something I'd expect the average climber to know. |
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kennoyce wrote: Just a few points, White doesn't necessarily mean that it's all dyneema, but colored definitely does mean that it is not dyneema. Dyneema can't be dyed and is only available in white and recently black, though the black is not used in any climbing gear that I know of. Generally speaking, in climbing products that claim to be dyneema, yes, the white portions are dyneema and the colored portions are nylon. As far as the strength is concerned, most slings are only bar-tacked to be rated to 22 kN. Most likely on a thicker sling they could add more bar-tacks to get the strength up higher, but they don't do that because more strength just isn't necessary for climbing gear and 22 kN is what is required for UIAA certification. I do agree however that most likely the weave isn't the issue. The more abrasion resistant "weave" obviously has much more nylon in it which is more abrasion resistant.Could you explain to me how nylon is more abrasion resistant? with dyneema being more slippery and having a higher tensile strength i don't see how it's more abrasion resistant. i believe nylon slings have better abrasion resistance for a few reasons. 1. They are thicker. 2. They use a tighter weave preventing crystals, noses of wire gates, etc from literally pulling the slings apart piece by piece. To Dan, it's pretty common knowledge i would expect 90% of climbers to know that dyneema is white and only white. |
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Dan.K wrote:Kennoyce, not challenging your point here that dyneema is not colored, but simply curious as to how you know that?I'm an aerospace engineer and have worked quite extensively in composites where dyneema is used frequently, but yeah, the fact that you can't dye dyneema is fairly well known among your average joe climbers as well. |
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Dan.K wrote:not something I'd expect the average climber to know.In the UL backpacking world it's not uncommon to see Dyneema being used in fabrics, and thus every so often someone will wonder why it's not available in other colors, or someone making their own gear will ask how they can dye it. |
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that guy named seb wrote: Could you explain to me how nylon is more abrasion resistant? with dyneema being more slippery and having a higher tensile strength i don't see how it's more abrasion resistant. i believe nylon slings have better abrasion resistance for a few reasons. 1. They are thicker. 2. They use a tighter weave preventing crystals, noses of wire gates, etc from literally pulling the slings apart piece by piece. To Dan, it's pretty common knowledge i would expect 90% of climbers to know that dyneema is white and only white.Thinking about it a bit more, I think you're right. Dyneema should be more abrasion resistant if you were to control the two variables you mentioned (weave and thickness). I'm not 100% sure on this, but I believe that the actual fiber diameter is thinner on dyneema vs nylon which means that when a single fiber of dyneema gets snagged on a crystal or sharp spot on a biner or whatever it is more easily cut. I may be wrong on this though. I was just thinking that nylon was more abrasion resistant based on anecdotal evidence without taking into account the weave and material thickness as you mentioned. |
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Regarding abrasion resistance, I see: |
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Jeremy B. wrote:Regarding abrasion resistance, I see: Fibres with high elongation, elastic recovery and work of rupture have a good ability to withstand repeated distortion; hence a good degree of abrasion resistance is achieved. Nylon is generally considered to have the best abrasion resistance, followed by polyester, polypropylene (Hu, 2008) - Analysis of Abrasion Characteristics in TextilesGood point, I hadn't thought of that, but it makes sense, dyneema is a much more brittle material than nylon which would certainly make it less abrasion resistant due to the fact that individual fibers would be more likely to break instead of just deforming. |
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that guy named seb wrote: Could you explain to me how nylon is more abrasion resistant? with dyneema being more slippery and having a higher tensile strength i don't see how it's more abrasion resistant. i believe nylon slings have better abrasion resistance for a few reasons. 1. They are thicker. 2. They use a tighter weave preventing crystals, noses of wire gates, etc from literally pulling the slings apart piece by piece. To Dan, it's pretty common knowledge i would expect 90% of climbers to know that dyneema is white and only white.Well I guess I outed myself as part of the 10% who didn't know...but no longer! To kennoyce, thanks for satisfying my curiosity. I enjoy a good technical discussion and have found this thread worthwhile. |
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Dyneema can be colored, but usually by coating, not by dye. |
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Jeremy B. wrote:Regarding abrasion resistance, I see: Fibres with high elongation, elastic recovery and work of rupture have a good ability to withstand repeated distortion; hence a good degree of abrasion resistance is achieved. Nylon is generally considered to have the best abrasion resistance, followed by polyester, polypropylene (Hu, 2008) - Analysis of Abrasion Characteristics in TextilesThat link you have sent isn't looking at dyneema only nylon and polyester, also even if dyneema is less abrasion resistant i think we are more looking for cut resistance and a good surface for our slings, practically the standardized abrasion test has little to no bearing on slings or even most outdoor gear, a good example of this is i saw on rope test lab simulating "realistic" but standardized tests on ropes and polyester destroyed nylon in the results polyester lasted well over double the time the nylon ropes lasted. I have also seen standardized tests on dyneema ripstops and shortly after the test was started all that was left was a dyneema skeleton. |