Cuben Fiber really stronger than steel?

[OneClick]

"Stronger than steel" is clearly a marketing phrase, which while likely true, does not mean what the average layperson thinks it means.

Exactly! I couldn't think of a way to say this, or even provide evidence. But you're right. It's like the "spider web is stronger than steel"...is it steel? I forget, but it's something like that. Maybe if you're talking per weight or volume, but that's rarely the case.

Reminds me of when these survivor shows say some bug has more protein per gram than a t-bone steak. OK, maybe if you can find 400 identical bugs to make up that same amount of steak. Still just playing on words.

[Stubbed my toe]

When comparing DSM Dyneema to Steel cable you get the following benefits:
More than 2x the number of bends (kinks) before replacement is due.
Dyneema is 15% of the weight of same diameter steel cable.
No risk of Frays/Hooks causing a cutting risk to your hands
Less energy stored (stretch) in Dyneema under tension so there's little risk of snap-back hazard should the cable break.
Comparing direct tensile strength is not helpful since there are MANY types of steel with varied strengths.

Bottom line for our application means light weight gear that is very strong and at least reasonably durable.

[MattK]

Specifically on RSBTRs website, the phrase "15x stronger the steel" is specifically refering to the Dyneema ripstop within the cuben fiber laminate. The poleyester it is sandwiched between is not as strong as steel. Additionally, it is important to note that the "15x stronger" metric applies only to tensile strength, not compression, shear, etc. It makes sense that this would be the metric, as tarps, flys, bags, etc, most often are subject to tension when used in the field.

Abrasion resistance is an important factor as well, however. In this case, if you compare similar weighted silicone impregnated nylon/polyester of comparable weights, cuben fiber is generally as abrasion resistant if not more than its more conventional counterparts, in addition to having a much higher tensile strength and tear resistance. For instance, classic silnylon is about 1.4osy. Cuben fiber of the 1.4osy variety is incredibly strong and very very abrasion resistant. A lot of thru hikers use this type of cuben for their backpack material with good success.

That said, RSBTR and other vendors continue close the gap with new fabrics and coatings.

[TrailSlug]

Is Cuben Fiber stronger than steel. Try this simple experiment. Poke your Cuben Fiber tarp with a steel knife blade and see which wins It's all advertising speak but don't let this worry you it's still a lightweight fabric if that's what you want/need.

[Just Bill]

Specifically on RSBTRs website, the phrase "15x stronger the steel" is specifically refering to the Dyneema ripstop within the cuben fiber laminate. The poleyester it is sandwiched between is not as strong as steel. Additionally, it is important to note that the "15x stronger" metric applies only to tensile strength, not compression, shear, etc. It makes sense that this would be the metric, as tarps, flys, bags, etc, most often are subject to tension when used in the field.

Abrasion resistance is an important factor as well, however. In this case, if you compare similar weighted silicone impregnated nylon/polyester of comparable weights, cuben fiber is generally as abrasion resistant if not more than its more conventional counterparts, in addition to having a much higher tensile strength and tear resistance. For instance, classic silnylon is about 1.4osy. Cuben fiber of the 1.4osy variety is incredibly strong and very very abrasion resistant. A lot of thru hikers use this type of cuben for their backpack material with good success.

That said, RSBTR and other vendors continue close the gap with new fabrics and coatings.

Took 3 pages to get the right answer?

It's not advertising- but you could potentially see it as "selective facts".
Tensile strength (along it's axis) of the strands is all it means- and in cuben- the "grid" you see is the only thing that is made from Dyneema. Which in fishing lines, ropes, and thread used to weave fabric is all stronger than steel in tension, which is why all our suspension pieces have such ridiculously high load ratings for such small little ropes. In shear (across it's axis)- good luck cutting a 7/64" piece of steel wire rope with a scissors even though it's an easy cut in Amsteel.

Cuben is basically a bug netting made of dyneema laminated between sheets of plastic. The plastic is not dyneema, nor is it anything but the means of laminating the loose fiber grid into a sheet of material. It's basically a glorified sheet of plastic.

A .51 ounce CF is very strong for what it is, and the dyneema grid gives it quite a bit of tensile strength.
As mentioned though, until you get into at least a 1.0 or 1.4 osy higher weight where there is more layers of material- abrasion is pretty poor- and punctures are pretty easy.


I know a fella who tried making some CF wind/rain pants- he shredded them up just from the friction of walking around with them on... something that Membrane 10 at .67 ounces can handle easily. It was the laminate itself that broke down, not the dyneema. But you could probably crank the hell out of a well made CF tarp RL in .51 oz to much higher tension than you could a .67 oz tarp.

CF is pretty neat- but as mentioned many folks have closed the gap on weight alone making it a bit easier for most to balance the total package of the material you select. The fabric came from the racing boat (sailboat) industry to give you an idea of it's original intended application.
CF is a good SUL choice for tarps and shelters... Even Z-packs (the kings of CF) have mainly switched to "hybrid" Cuben fabrics for their packs to balance strength and wear. Of course that stuff is now up in the 3osy range so... not sure what the real point is when you could get a good PU coated Hex 70 at 3.2 oz for $6.75 yd and beat the hell out of that stuff.

The material has always been very expensive, and the original company had some equipment failures that led to a shortage of material for a time as well. They did allow minimum orders as small as 9m.
The company has been bought out as mentioned so in theory the supply issue should be solved, however I can't comment on pricing changes or MOQ from the current owner... but attempting to stock $25+ per yard material would be an expensive investment for any vendor in more typical 50-100 yard roll sizes, so that may explain why some folks called it a day on stocking it. Could also have been as simple as many people have moved on from it for most projects.

To the OP- you could put a bumper of many types of materials on your bridge pole tips if you wanted to stick with the CF tarps.