Inferior weaves of dyneema slings

that guy named seb wrote: That 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.

Dyneema is less resistant to cutting. Although is has very good tensile strength, it doesn't resist compression very well. This is the same reason a knot will generally derate a Dyneema cord more than a nylon cord.

It also has less resistance to fatigue cycling.

that guy named seb wrote: 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.

Brian L. wrote:Dyneema is less resistant to cutting. Although is has very good tensile strength, it doesn't resist compression very well. This is the same reason a knot will generally derate a Dyneema cord more than a nylon cord. It also has less resistance to fatigue cycling.

that guy named seb wrote:There seems to be two types of weaves for dyneema slings cdn.outdoorgearlab.com/phot… this picture represents it best, the one on the right seems to be the standard for skinny slings (from what I've seen) annd the one on the left is for wider slings and my question is, Why is the one on the left not used universally? I ask this because all my sling with the weave of the one on the right seem to be a hell of a lot less durable than my slings with the weave on the left, is some strange form of engineering in a reverse bell curve for slings? I would like to think that they did it that way because by the time the sling looks tattered enough to replace it the dyneema is past it's use by date but it seems like it wears to quickly to do so. Has anybody had the same experience as me and/or tell my why they use this specific weave for the slings?

Dan.K wrote: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.

It looks like both are actually the same weave, though it appears that they have a difference in the concentration of weft strands. The color variation is a natural product of the weave by laying the warp strands in the appropriate manner. It is possible they are different weaves and just look very similar, but I doubt it.
So as others have pointed out the difference in durability is likely do to a difference in materials. If you go to any cord manufacturer it is common knowledge that dyneema has less abrasion resistance than nylon. Abrasion resistance has little to do with the coefficient of friction as the abrasion is generally going to come from it snagging and cutting/breaking (talking about individual filaments rather than the whole cord/tape and again while dyneema is stronger than nylon it is also more brittle so can still break easier under the right circumstances). Nylon has more stretch and doesn't cut/break as easily so it can take those snags better and is thus more resistant to abrasion, and again the fatigue plays into this as well.
Most of this has already been said, just more explicitly pointing out how all the aspects are connected.

Brady3 wrote:It looks like both are actually the same weave, though it appears that they have a difference in the concentration of weft strands.

They both look like they are done as a "sword mat" (knot #2964 in the Ashley Book of Knots, I can't find a link with a good picture though). But this is just based off the picture in the OP, I haven't bothered to get out my slings and look at them so I could be wrong.

EDIT: The one has a twill look just because of the way the colors are laid, it might have a bit more of twill weave to it but not necessarily. It still wouldn't be woven like twill fabric is, that's obvious by the fact that the slings look the same on both sides (think of how your jeans are lighter on the inside, that's because the weft and warp yarns are different colors. The sling has alternating colors in the warp and colored weft yarns that are only visible on the edge which is more similar to the sword mat plat)

Ah yes, the sword mat does look correct. Google Books has an image from Ashley. Thank you for the name; I wouldn't have known it otherwise!