Podcast 002 | Dyneema Composite Fabrics

[Backpacking Light]

Companion forum thread to: Podcast 002 | Dyneema Composite Fabrics

In this episode, we dive into the design, manufacturing, and applications of Dyneema Composite Fabrics.

[James Marco]

The cost of DCF is simply phenomenal. And yes, I agree totally that the lack of stretch is a benefit and a detriment. Good overall review. Thanks!

[J-L]

This was well done. I enjoyed hearing the differing views from the cottage gear founders.

Do you see any advancements on reducing the packed size of DCF shelters? I really like how easy it is to stuff silnylon shelters and how small they pack. I have to carefully fold or roll my DCF tarp to get it to a reasonable size.

[Mario Caceres]

Nice job.  Thank you for putting this together.

[Brook / MtGL]

It’s interesting to see the different comments by cottage manufacturers… just wonder, why MLD is not invited.

[Richard Russell]

That was an excellent podcast. Well done! Must have taken a good bit of work to set all that up. Looking forward to more like this.

[James Marco]

Yes, as John H was saying, some info on packing DCF would be good. I typically shake it off, fold and roll it into it’s bag. This generally leaves a fairly largish bag about 1.5L to 2L. It is a ZPacks Solo+ and weighs about 17oz. This always requires it’s own bag to prevent wear/abrasion while carrying it. It also requires a few extra stakes.

As I said elsewhere, my tarp is silnylon, weighs 17oz and generally rolls and fills my grease pot (about 1L.) This is a two person tarp. Because it fits into my pot, I don’t need an extra bag for it, and only needs 6 stakes.

Needless to say, I rarely use the Solo+. Only in mosquito season (following on the heels of blackfly season) does it become important to keep bugs off. The extra volume(larger size) usually means a slightly larger pack (15oz Miniposa vs. 13oz Murmur) so the overall pack weight actually goes up slightly with the DCF.

If you have any trick to make the volume smaller I would be much interested.

[Ron Bell / MLD]

Reply to above question about MLD not in the podcast:

BPL was very nice and did ask MLD/Ron Bell/Me to be part of the podcast. I was out of the country with iffy phone service during the time they needed the interview for the production deadline and so it was not possible.

I did listen to the whole podcast and found it interesting and informative for many DCF users.

BPL/Ryan was a pioneer in DCF backpacking gear.

MLD is the oldest company now to offer cuben fiber backpacking equipment and was part of those very early days developing gear and construction techniques. BPL did offer the first products for a short time, made for them by another company that does not offer DCF products. We started building gear very shortly after BPL and never stopped. A few may remember our first Cuben Fiber/DCF pack, a 2.9oz Prophet, the first available DCF backpack.

The #1 Question we get about cuben/DCF is “I’ve read on the internet…”

We always answer that it depends on the type of DCF they were reading about and how old/accurate is the information. There are so many DCF types and each type has a best use for different equipment and adventure goals.  The bottom line is that there is a type of DCF  that is almost always the best fabric for most all backpacking gear at a given weight.  No other 3oz pack fabric is as tough and strong as 3oz DCF.  The same for .8 DCF in shelters. But DCF does cost more.

The #2 Question is how long will it last?

Again, depends on the type DCF. The most common use is the .7/.75/.8 oz sq/yd type for shelters and its the primary type we use – the CT2E.08.  We say that the same Mid in .75 DCF will last about 200-250 nights and our very high quality  1.5oz 30d Pro SilNylon about 400-500 nights. (Note that lower rated (low HH) common SilNylons and light Sil/PU Poly/Nylons would not last that long.

 

NOTE: EDIT BELOW ADDED FOR CLARITY:

As noted above – the common DCF used in shelters is very durable and extremely strong.  The long term durability is equal or better  than most all of the hundreds of sub 1.3oz-ish shelter fabrics (silnylon,silpoly, poly/sil+PU, etc.) we have seen and tested and definitely as durable – and far far stronger – than all sub 1.1oz shelter fabrics of any type. The few very high quality 1.3oz + SilNylons can last longer at almost double the weight.  Many  DCF .75 shelter  users will get much longer than 250 user days/nights.  See below for a value analysis.

The Cost of DCF in a Shelter/Gear:

Think of any gear in terms of the cost per user day.  A $500 DCF Mid would cost about $2 per day of use or half a Starbucks per day. If you are more of a Dunkin Donuts coffee person, the Pro SilNylon is about $1.  They are both excellent shelters but the DCF does weigh about 25% less and can have a few other  performance gains depending on your application.

Bonding or Sewing:  We’ve been doing this for a long time. Longer than anyone else. Our lede DCF craftsman has been doing it for almost 10 years now and me even longer.  Bonding has to be done correctly. The right pressure using the right tool to create enough burnishing heat. The proper seam width  for the application and even the handing and storage of the transfer tape/adhesive around the shop is important.  All of our bonded main seams are a full 1″ wide and any seams on a significant bias (the long Mid corner seams) are then over taped with DCF oriented in-line with the seam to prevent bias stretch along that seam. (You just learned a secret technique we developed!)  Some other parts are sewn and then over taped/bonded to seal and strengthen that area.

The skill and hand work / training required is a big part of the cost and for now is the main reason that it is hard to mass produce DCF gear at a lower cost.  It can not be outsourced to China yet. This is mainly why gear companies that do not build in-house do not offer DCF products. ( There are few small exceptions.)  The margins and price mark up is not there for them to compete and make a profit. If it were they would use DCF because it is far stronger, more waterproof and lighter vs light silpolys or very low HH WP coatings that are used to get to low weight to try to complete.

Thanks to BPL for the podcast and helping to educate about DCF.

 

 

 

 

[Andrea W]

I have listened to both podcasts and found them fascinating with a wide variety of views and information.  I decided to subscribe to the website after listening to the last podcast.

Thank you for your hard work putting the podcasts together.

[Brook / MtGL]

Dear Ron, you gave more insights into DCF regarding the cost, taping against bias etc. Great thanks!!! I agreed that, because of the really unique properties of DCF, a DCF master piece should should have its uniqueness in craftsmanship AND the inherant design – both cannot be replicated by any other “traditional” fabric. And also because of these, DCF even fits into cottage making better, and are not suitable for mass production at the moment, hence the very reasonable high price.

 

 

[James Marco]

Ron, while you mention that silnylon lasts about twice as long as DCF products, this does not jive with my experience with the stuff, or, maybe it does…

Do you have any parameters for the failure modes? I am not sure what you are talking about. In strength, DCF will maintain itself better than silnylon. However, the inevitable leaks (usually starting with small pinholes then progressing to more of them) doesn’t seem to heavily effect the overall strength. But, a largish area of pinholes or delaminated membranes is nearly impossible to repair. Is there any plans for releasing the adhesive in larger sheets that could be ironed on these areas or other form of repair?

Silnylon is subject to UV damage. My tarps are typically coated with a light coating,~20-30:1, of mineral spirits and silicone. Every three or four years I re-do the coating. This has the effect of building up weight but mitigates the UV damage. The overall weight is only effected about .1oz/sqyd after coating or maybe an ounce or two, total. So, like a car, maintenance is important.

I am not sure if the overall lack of durability of DCF is offset by the increased longevity of silnylon.

[Gunnar H]

Great podcast! Thanks.

[NoCO-Jim]

Good podcast…appreciate the info.  Wonder where DCF will be 5 years from now?

[William N]

Great discussion.

My two cents. Where will DCF be in five years? Probably being mass produced at a lower price overseas with further development stopped dead in it’s tracks. Products will be marketed instead of ‘fitted’ . We want the best tools, the best gear;  not whatever had the best brochure, or the most ‘features.’

[Beendarenback]

I too appreciated the podcast to clear up one misconceptions about the DCF fabrics.

 

It seems to me the failures we hear about on the forums are primarily due to the Mylar[ type] coatings. Is that accurate?

I didn’t realize there are many different coatings used on these fibers

[Thomas Willard]

With regards to where DCF will be in 5 years posted by William? I believe it will be exactly where it is now: niche product. We thought 5 years ago it would’ve been mass produced, especially since that’s when Zpacks really began to explode in popularity.

[Anthony A]

Never thought I would listen to people talk about fabric engineering…. but I really enjoyed this episode and it helped me better understand this crazy fabric! Keep up the excellent work guys!

[Hanz B]

Hi,

I’m really interested in the idea of a Dyneema mesh to replace no see um. My initial thought is that the no see um  is now the heavier material on an UL tent. I wonder if some sort of loose weave Dyneema mesh would be lighter, more tear resistant, and keep its shape.

Then again maybe the give you get from no se um mesh is important in the otherwise unforgiving DCF shelter. I notice my mesh is often stretched a bit in some odd direction a little differently everytime I set up a DCF tent.

I guess the other thing to think about is that no seem um mesh tends to hold onto morning dew and water, which i suspect is an interaction between capillarity action the humidity in the tent. Ideally you want most of it to pass through to the DCF walls and drain down. Correct me on that if I’m wrong.  So would swapping out a no see um mesh for the hydrophobic Dyneema strand mesh change that? My thought from what I remember in college is any hydrophobic channel forces water vaper to one side or the other. In the construction of a tent would this mean more water dripping down on me or more water escaping given the same humidity temp parameters when comparing a theoretical dcf mesh to a no see um.

Then what about the construction mechanism? Would it just be a woven loose pattern with proprietary adhesive. Or some sort of heat treatment the melts the weave together?

[Craig]

Re the tongue in cheek questions and views in 2018 wondering if DCF would still be here in 5 years
April 2022 -still in use highly successfully by cottage manufacturers (admittedly there are recently new fabrics that are even more sophisticated and might make a dent finally) 🙂.

Its interesting to go back 5-10 years and read stuff and compare.

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