Fabrics, Materials and Pack Construction

SWD is now building packs with several new fabrics from the ECOPAK line by Challenge Sailcloth: EPX200, EPX400, EPL200 Ultra, EPL400 Ultra, and EPL800 Ultra. I've had a chance to test some of them this year and am impressed so far. But I began to realize that some people often don't understand the possible benefits of these new fabrics when I try to explain them. With that in mind, the purpose of the following paragraphs is to answer these questions: Are the ECOPAK fabrics really any better than X-Pac or DCF? If so, how are they better?
Out with the X-Pac
Superior Wilderness Designs has been using X-Pac VX07 as their standard light and inexpensive fabric for a long time. Made by sailmaker Dimension Polyant, X-Pac VX07 has a 70d nylon face laminated to a polyester x-ply, a 0.25 mil polyethylene terephthalate (PET) waterproof film, and a 50d taffeta backing. It weighs 4.8 oz/yd².
SWD also used X-Pac VX21 and VX42 on their rugged packs. X-Pac VX21 has a 210d nylon face and VX42 has a 420d face. These face fabrics are also laminated to an x-ply, a 0.25 mil film, and a 50d backing. The VX21 weighs 6 oz/yd², and the VX42 weighs 8.4 oz/yd². Abrasion resistance, measured using the Taber D3884 abrasion test, is 500 cycles for the VX21 and 1,700 cycles for the VX42.
Out with the DCF Hybrids
SWD has been using DCF hybrids on the ultralight versions of packs. DCF, previously known as Cuben Fiber, is a laminate fabric consisting of crisscrossing strands of Dyneema or ultra high molecular weight polyethylene (UHMWPE), sandwiched between thin polyester films. To use this fabric on packs where more abrasion is expected, a 50d or 150d plain-weave polyester face fabric is laminated to it. The 50d version weighs 2.92 oz/yd² and the 150d version weighs 5 oz/yd². On the Taber abrasion test, the 50d registers 500 cycles.
And in with the ECOPAK EPX
The X-Pac fabrics have been replaced by two exceptional fabrics from Challenge Sailcloth, ECOPAK EPX200 and EPX400. Most importantly, the EPX fabrics are made from 100% recycled polyester components. This is a big deal because the energy used to recycle polyester is far less than the energy used to create new nylon. Moreover, the type of nylon that X-Pac is made out of--nylon 6.6--is essentially impossible to recycle because it is constructed from two different molecules. Experts refer to the attempt as trying to unbake a cake.
EPX200 has a 200d polyester face fabric and the EPX400, as you might think, features a 400d polyester face fabric. Beneath the face on both fabrics, there is a 45° CrossPly, and sandwiched on the other side is a 70d ripstop backing. This ripstop backing increases seam strength considerably, in comparison to X-Pac seams. The EPX200 weighs 5.9 oz/yd² and the EPX400 weighs 8.95 oz/yd². Abrasion resistance on the EPX200 is about 500 cycles, whereas it's a very impressive 3,000 cycles for the EPX400.
Reasons for Switching to ECOPAK EPX fabrics
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EPX is made from 100% recycled polyester components, so it is better for the planet
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Far less energy is used to recycle polyester than to create new nylons
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Every yard of ECOPAK saves over one pound of CO2, compared to nylon pack fabric
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CO2 emissions from manufacturing this recycled polyester are 50% lower than nylon
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ECOPAK contains no harmful TPU, PVC, DWR, or other coatings
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EPX has better abrasion resistance than X-Pac
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EPX will increase the seam strength of the pack
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EPX has a similar weight to its X-Pac counterparts
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The overall cost of the pack remains about the same
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EPX is 100% waterproof just like X-Pac
And in with the ECOPAK EPL Ultra
The DCF Hybrids have been replaced by some really impressive fabrics from Challenge Sailcloth: ECOPAK EPL200 Ultra, EPL400 Ultra, and EPL800 Ultra. You may sometimes hear people referring to these as UltraWeave or sometimes just Ultra. The face of these fabrics is woven 200d, 400d, or 800d UHMWPE. This is laminated to a 0.5mil polyester film for waterproofness and to keep the weave of the face from shifting around. This film is 100% recycled and has excellent UV resistance.
The EPL200 Ultra will be replacing the 50d DCF hybrid on SWD's ultralight packs. It weighs 3.5 oz/yd² to the 50d DCF's 2.92 oz/yd², so it is only ever so slightly heavier. Pair that with the fact that the Ultra 200 tested to an amazing 3,800 cycles on the Taber test, whereas the 50d DCF is around 500 cycles.
Made from EPL400 Ultra and EPL800 Ultra, the new Rugged Long Haul 50 is seriously bombproof
The EPL400 Ultra (4.65 oz/yd²) will now be used for the body of SWD's rugged packs because it is actually a little bit lighter than the 150d DCF (5 oz/yd²) and significantly lighter than the VX21 (6 oz/yd²), or the VX42 (8.4 oz/yd²) previously used. EPL400 Ultra tested to a ridiculous 7,600 cycles on the Taber test, which is far higher than anything yet mentioned. The EPL800 Ultra will be used for the bottoms of these rugged packs. It weighs 8.1 oz/yd² and went an absurd 10,500 cycles on the Taber test.
Reasons for Switching to ECOPAK EPL Ultra fabrics
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EPL Ultra has far better abrasion resistance than either X-Pac or DCF hybrids
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The overall cost of the pack remains about the same as packs made with DCF hybrids
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It is lighter than either X-Pac and DCF hybrids
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100% waterproof just like X-Pac and DCF hybrids
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EPL Ultra is made from 33% recycled polyester components, so it is better for the planet
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Far less energy is used to recycle polyester than to create new nylons
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Every yard of ECOPAK saves over one pound of CO2, compared to nylon pack fabric
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ECOPAK contains no harmful TPU, PVC, DWR, or other coatings
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CO2 emissions from manufacturing the recycled polyester used for the film backing are 50% lower than nylon
Foam
Our shoulder straps and hip belt wings are made out of 1/2" thick evazote foams. These are the most resilient and longest lasting foams that we can find. They will give you many years of use without flattening out. We use varying weights and densities of foam depending on the application.
Shoulder straps and hip belt wings are made out of a 420D Robic nylon for maximum tear resistance.

Backpack Construction
Our packs are hand-made by us right here in Michigan and are constructed using the finest materials and the best construction methods. These packs are ready to handle anything you can throw at them, and will give you thousands of miles of use. All stress points are reinforced and bar tacked. Our packs are very water resistant and are made out of completely waterproof fabric. Ultra packs have the option of seam taping for extra water resistance. EPX packs can be seam sealed using a liquid sealer such as Seam Grip.

