Modern Pack Fabrics: Creating a standardized test for abrasion and wear.

Nathan, you might take a look at this link from Hill People Gear.  He tests a bunch of fabrics, including X-Pac, hybrid cuben, dyneema, and several others.  I found it fascinating.

[edit]I was about to post this link, but procrastinated — until your question brought it to mind again…

The Martindale abrasion test is standard for textiles. There are ASTM, DIN and other Standards for abrasion. It’s all very known technology from nigh on 100 years ago. There are NO excuses for not using the Standard.

Sadly, I have to add that I have noticed that quite a few American pack manufacturers seem to avoid testing to recognised Standards. They make up their own, which are usually a bit deceptive. And you also get the famed Backpacker Magazine test, which consisted of towing a number of packs along a road behind an SUV.

Cheers

years ago our famous mistah caffin did a SOTM report on packs

there was basically little to no correlation between the fabric type and thickness … and the overall weight of the pack

the features and all the other goodies ate up any weight savings

now if one was to make just a simple bag with 2 straps i could see a decent difference … but even the the VERY well reviewed dead bird alpha FL 45 is one of the lightest alpine packs (bag with very little extra features) around (i own one) and even it uses 400D+ fabric @ ~670g

if one wants a hard wearing abrasion resistant pack ,,,, simply get a climbing pack, you can find quite a few thats reasonably light

personally i think worrying about abrasion resistant fabrics (except for the bottom) is overkill on “walking” packs …. most folks use packs with large amounts of mesh anyways, and those will get chewed up way before the fabric

;)

Valerie, Thanks! That link is very helpful. Though, looking at the 150d Cuben numbers, I have suspicions about how that test translates to real world wear and tear.

Roger, thanks, I’ll look into these standards and procedures.

Eric, I’ve seen Cuben and 140d Dyneema Gridstop packs ripped to shreds by ‘walking’ through manzanita.  Following your reference that fabric type and thickness have minimal effect on pack weight, would it not make sense to build a pack from more rugged fabric, if only for piece of mind?

+1 to what Nathan said. Good find Valerie and thank you for sharing.

“Following your reference that fabric type and thickness have minimal effect on pack weight, would it not make sense to build a pack from more rugged fabric, if only for piece of mind?”

There are other options besides the ones mentioned or the ones tested.  As far as durability to weight factors go, probably nothing beats pure/100%, woven UHMWPE fabric made from the highly oriented fibers.  While Spectra and Dyneema based fabrics are probably the best quality, the less expensive, direct from China stuff is probably still pretty decent.  I got some for around 27 dollars and for a meter x 1.6 meter wide–2.4 oz/yd2 stuff–“free shipping” too (i’m sure they figure it in in the cost of the material).

The problem with all of the above PE based fabrics though, is UV degradation and slipperyness of the fibers (the weave or knit can lose stability and start coming apart some).  And maybe the white color for some folks. To deal with the first two issues, i plan on laminating some 1.4 Silpoly PU4000 to the outside of the UHMWPE fabric, and sewing around the edges and in a X pattern.  The spray adhesive i got says it’s good for polypropylene, so i’m hoping it works ok for the PE, since they have similar surface energy.

I don’t expect the 1.4 Silpoly to last super long (since it’s going to be on the outside), but it will give a real boost to the overall longevity and durability of the pack material via helping the above 2 issues.  So 3.8 oz/yd2 for the fabric, and round up to about 4 oz/yd2 including the spray adhesive and extra stitching.

Should it actually work well in practice, then it would be a pretty decent weight to durability to cost ratio.

<span class=”Apple-style-span”>Eric, I’ve seen Cuben and 140d Dyneema Gridstop packs ripped to shreds by ‘walking’ through manzanita.  Following your reference that fabric type and thickness have minimal effect on pack weight, would it not make sense to build a pack from more rugged fabric, if only for piece of mind?</span>

if youve ripped the cuben, then your mesh is likely  in tatters tooo .. using these UL packs for bushwhacking is simply the wrong application … in fact outdoorgearlab (and some BPLers in the past) have indicated that the HMG packs are not as abrasion resistant as some other climbing packs

how much material does it take to make a “normal” pack BPLers use … 1-2 yds?

which means that if one really wanted to one could make a much beefier pack it would weigh an extra few oz all other things being equal

however as long as you have large mesh pockets there isnt too much point in it

;)

Justin, got a link to that UHMWPE fabric resource? Assuming it is uncoated. I thought that those fibers were quite UV stable?

In conversations with Dimension Polyant about custom fabric builds, they mentioned that the D40 isn’t full UHMWPE(it has a polyester warp) because they were having lots of issues getting the PET laminate to stick to the pure UHMWPE.

Back to the original topic, do slippery or low-friction fabrics have the capacity to skew results from tests using the Martindale machine, or the Taber abrader?

Also, how do these tests translate into real-use durability? I still believe firmly based on my experience that Xpac is more durable that Cuben Hybrid at a similar weight but the numbers from that link would seem to disprove my belief. Is there something missing here?

In conversations with Dimension Polyant about custom fabric builds

Does it still is pretty undoable regarding cost, etc… ?

Hi Nathan,

I’m not sure how to cut this link down, but here it goes:
http://www.aliexpress.com/item/Free-Shipping-200Denier-Fiber-80g-m2-Tear-Resistant-Plain-UHMWPE-Woven-Fabric-Raw-White-Cut-resistant/32260352447.html?spm=2114.30010308.3.2.zZ1R6v&ws_ab_test=searchweb201556_2,searchweb201644_5_505_9890_506_503_504_301_502_10014_10001_10002_10017_10010_10005_10006_10011_10003_10004_10009_10008,searchweb201560_5,searchweb1451318400_-1,searchweb1451318411_6452&btsid=69a4715b-c211-46cc-b141-cf2f18937c48

As an alternative, go to aliexpress and type in “UHMWPE Fabric” into the search, and you’ll see one listed that costs 27.08 and weighs 80 grams per square meter.  That’s the one i purchased and received. I thought it would be more open weaved or knitted based on weight and denier, but it’s tighter than i expected, though hopefully i should be able to sew through it.

Perhaps the Dyneema and Spectra brand fibers are decently UV stable because they may add UV handling additives (especially to their rope/cord etc), but the basic material has poorer UV handling characteristics than nylon.  (something like silnylon is improved by the outer coating of silicone which is pretty UV stable and absorptive).

This is why i chose a polyester fabric with an outer silicone coating, because both polyester and silicone have good properties for UV. It’s just a sacrificial layer.

“In conversations with Dimension Polyant about custom fabric builds, they mentioned that the D40 isn’t full UHMWPE(it has a polyester warp) because they were having lots of issues getting the PET laminate to stick to the pure UHMWPE.”

I’m not surprised, and i suspect that while the adhesive i got says that it’s appropriate for low surface energy plastic like polypropylene, it may not work so well long term.  That’s why i’m also sewing all around the edges and then in an X through both fabrics to help stabilize it mechanically as well (i’ll have to put silicone on the outside fabric). I also plan to rough up the fabrics a tiny bit with sand paper. The adhesive i’m using btw is this:
http://www.loctiteproducts.com/p/a_cntct_pro/overview/Loctite-Spray-Adhesive-Professional-Performance.htm

edit p.s.– I received the fabric in about two weeks.

RE: X-Pac fabrics:  Of course, this is only my experience (not a study), but I MYOG’d an X-Pac backpack, and thru-hiked the CT (almost 500 miles), and the bag still looks new.  I’m fairly careful with my equipment, and only bushwhacked above tree line on the trip, but there were occasions when I had to push my way through overgrown willows.  It was completely rain-proof, too.   I never dragged it behind my Honda Civic, though… ;^)

I would not hesitate to make another bag with X-Pac.  The stuff is “bomber”.

Edited to add:  As Roger mentioned, below, I also used the heavy-duty cordura X-Pac for the bottom of my pack (maybe a weight penalty of 0.5 oz?).

I use X-Pac on my MYOG packs too. It works very well.
Yes, I did use a heavy Cordura X-Pac for the base – it added very little extra weight.

One of the reasons X-Pac works well IMHO is that the laminate inside it prevents the weave from snagging on pointy stuff, so the fabric slides off things rather than catching.

Sewing: for UHMWPE fabrics, you must use more complicated seams with fold-overs, to prevent the weave from pulling apart.. But the same applies even to a loose-weave nylon ‘pack cloth’, so construction matters as much as materials.

Cheers

Unfortunately I didn’t have a wider variety of fabrics to send Luke for that testing project.  It’d be interesting to delve more deeply into the abrasion properties of the different face fabrics D-P uses.

If you look at the distinction Luke drew between minor and major failure, I think that in the field an abrasion bigger than “minor” would probably cause a significant tear under load.  I also presume the taber abrader wheel is quite a bit smoother and more uniform than anything you’d get in the field, which is why (for instance) the cuben film of the 150D hybrid lasted so long.  My field experience with that fabric is that once the face fabric is gone any pokey thing tears the film easily.

As Luke wrote: “Abbrasion testing leads me to believe that the Tabor results are biased towards slippery fabrics, the face fabric was stripped away rather quickly (1000 cycles? I didn’t record the exact number) and the cuben itself took a far more cycles to fail then what logic would suggest.”

The gridstop he tested was taken from a 2012 GGear Gorilla I had killed canyoneering, and the stats illustrate one reason GGear moved away from that fabric.

The diamond ripstop is the same stuff you can still buy from Rockywoods.

My quarrel with cuben hybrid remains the unjustified hype, and the cost.  The cuben film is obviously a bit superior than the D-P PET laminate in several ways, but I don’t think those differences are meaningful for actual use.  If 150D cuben hybrid were 25 bucks a yard I could see using it over VX21.

We (Seek Outside) have done a lot of fabric testing. In fact , Luke , mentioned in this thread, is very instrumental in our pack design team (he did the testing project well before he worked with us). Luke is a great guy, and very passionate about packs, and we are glad he is a part of our team.

Anyway, we have as our basis , the testing that Luke did, taber specs from DP, real world feedback from customers, our own usage feedback, our own non scientific test (taking rocks and scraping various samples over and over) , and sometimes a destruction test or two. It is our feeling that DP fabrics, in real world usage, offer better bang for buck and longevity than others we have tried. While my personal preference, is the 330D / 420 D face fabrics, we have had very few issues with the 210 D face fabrics for most backpacking purposes. Sure, some fabrics, may come in a bit lighter, but personally, we don’t think they provide the long term performance value.

What I like to know is if anybody has noticed an evolution over time where a certain level of abrasion resistance is being met by ever lighter fabrics ?

Because I remember that even not so long ago 1000D-fabrics were being used for high weare areas, and now 500D-fabrics or a bit more are almost the heaviest used deniers in packs.

My feeling is that the expectations of “durability” are much lower these days

old packs were made to last … Many folks still htave “bomber” packs around, even if they were just daypacks folks expected them to take a beating

now with the disposable consummer culture, well just buy a new one every so many years

Folks are willing to sacrifice durability if it saves em some weight or has fancy features

i mean how much sense does it make to put “bomber” fabrics on a pack thats covered in mesh pockets and has a fancy ventilated mesh frame?

while there have been advances notably with dyneema packs …. The majority of packs sold are good old nylon, cordura or some variation thereoff

many rock climbing (not alpine) packs are still made of bomber fabrics … Theres no way to escape abrasion in that environment

;)

Good point of course but I wonder if their has been no change than brands lowering their standards ? I don’t know how it’s there but if here someone buys expensive outdoor gear, it’s not to buy similar stuff in just a few years.

Kevin Timm hit the nail on the head.

-X-pac is superior.

Because I remember that even not so long ago 1000D-fabrics were being used for high wear areas, and now 500D-fabrics or a bit more are almost the heaviest used deniers in packs.

I think (think, not know), that there are several factors here. The first is that fabric mfrs do their own testing, and they can improve (at least a bit) the abrasion-resistance of fabrics when the customer demands. Taslan fabric is more abrasion-resistant than plain nylon, but it’s still just nylon. Some of my Taslan clothing is 20 years old, and still going strong.

The second this is that a lot of old gear did not pay enough attention to design details. For instance, you often had these prominent square corners sticking out at the bottom of the pack, and those corners were always a focus for wear. Change the design so there aren’t those corners stickng out and you don’t get the wear at the corners.

Thirdly, even pack usage has changed a bit. Whereas a single pack once had to handle rock and extreme scrub as well as day walks, people now often do have different packs for different activities.

So it’s not all a downgrade imho.

Cheers

OK, although that’s mostly improvement in design and change in use. But somehow I suspect (and hope) that there is an improvement in the fabrics themself and that e.g. 680D today shows the same properties as 1000D then.

I mean, as a student, long ago, during one of my chemistry courses, we made polyamide/nylon by simply mixing two chemicals. So, it shows it’s not that hard, but I can’t imagine too that every kind of polyamide would be as simple to make.

I have a small day pack made of heavy weight Cordura that has held up amazingly well through sandstone slot canyon scrambling and dragging around in West Virginia’s caves and used on many hunting trips.

It shows signs of abrasion but no worn-through areas, unlike the medium weight, ripstop fabric on a Vaude pack that had similar treatment.

But somehow I suspect (and hope) that there is an improvement in the fabrics themself and that e.g. 680D today shows the same properties as 1000D then.

Not really sorta. with the same weave and denier, nylon 6 is the same as it ever was. Different weaves have come about (Cordura Brand for example) to help with strength/weight ratios. Implementing hi tenacity fibers can improve things over nylon 6 for additional cost.

Cuben excels in its tensile strength tests, and we love this stuff for shelters. This stuff was designed for racing sails, and its characteristics excel in those environments. Packs receive entirely different types of forces than do racing sails. Realizing this, Cubic Tech started adding a face fabric or protect the cuben laminate from abrasion. This is where it gets tricky because as the face fabric increases in strength/weight the strength(vs abrasion) of the cuben laminate becomes trivial in relation to the woven fabric. So, an application that requires a pack fabric beyond a threshold (I’d guess near 200 denier or 4 oz/yd2) Renders the Cuben providing increasingly diminishing returns.

One Benefit of the Cuben is it’s laminated nature, which provides ease of construction (due to the stuff holding creases when folded), as well as the capacity to be taped with rolls of hi strength adhesives.

Seam tapes can be built of laminated fabrics, such as X-pac or Cuben fiber for additional waterproofing and seam reinforcement.

Woven fabrics implementing high-tenacity fibers in excess of nylon or polyester can create a higher strength-weight ratios in areas of tear, burst and abrasion resistance.

A waterproof laminate such as those used on Xpac or Cuben fabrics provide more durable and lasting waterproofing vs Polyurethane or Silicone coatings.

Roger Caffin observed that the more complex(and heavy) a pack becomes, the less impact the fabric weight has on the overall pack weight. So a pack with lots of options is a good place to employ more durable fabrics to reap the benefits of this.

More durable pack fabrics make a lot of since because they last longer.

Many would prefer a pack that lasts years, vs a pack that needs to be replaced often.

For all of the above and more, it is my personal belief that Xpac fabrics are the best pack fabric option out there. (Unless you’re goal is pushing SUPAHULTRALITE/disposability ratios UP.. maybe for adventure racing? ;)

Cuben still remains the best fabric hands down for shelters and seam tapes. And racing sails…

But hey, don’t believe the Hype. Whats everyones experience?

How long does a pack in Cuben last? DyneemaX? Pack Cloth? 500 or 1000 Denier Cordura? Xpac?

And further, does data from current testing standards reflect real world wear and tear?

My wife and I have used 1.9 ounce per square yard uncoated ripstop nylon on our myog backpacks for at least a 10-15 years.  Gets pin holes and small rips (mostly on bottom) in it but hasn’t ever failed.  I’m sure it would fail the abrasion tests discussed here but it works for me for Pacific Northwest backpacking mostly on trails.  I replace the easy-to make-bags every few years.  Saves me about a quarter pound over the heavier fabrics.

My clothing is the same weight as the bag fabric or lighter and it holds up pretty well so I figured the 1.9 ounce nylon was good enough for me….and it has been.

I use the replaced bags around the yard to haul woody clippings, roots, rocks, blackberry cuttings, etc.  More holes and rips appear but still no failure.

I’ve experimented with incrementally lighter nylons and didn’t experience a major rip until I got down to stuff that was about 3/4 ounce per yard.

.

Thanks Daryl! Was that 70 denier nylon that’s 1.9oz? What about coating? PU or sil? Is the .75 oz stuff around 10 denier? Ripstop weave?

Nathan,

Yes, on the deniers and yes on the ripstop.

I use uncoated fabric.  I rely on internal plastic bags to keep things dry inside the pack that need to be dry and let the water run through everything else.  With uncoated fabric things drain easily and dry quickly.

After each hike I remove the uncoated pack bag from the pack frame and run it through the washer with my clothes.  I’m a heavy sweater and my gear stinks and gets covered with white salt residue on  trip.