In the last few months I’ve had impetus from several directions to hit the reset button on backpacks as completely as possible. Shake off and re-examine as many assumptions as possible before I put them into practice. This bag, and this post, are only a first step towards that end.
Problem 1: Seams are the enemy.
Seams create weak points and add weight, bulk, and (potentially) complication. Testing has confirmed my years-old assumption that burly fabrics will rip stitches, while weaker fabrics will rip from stitch hole to stitch hole. Tuning thread to suit the fabric and reinforcing seams can mitigate but not do away with these issues. The complication is that bag shaping is a vital factor in making a pack which carries, wears, and uses well. For the bag below I went back to the roots of the 610 pack and copied my original design as closely as possible. It sure carries well, and after a few years of love affairs with zippers its not so bad to have a simple top loader that demands some thought in packing, and doesn’t mind sand (this last highly relevant in the desert, and much less so in NW Montana). It would be possible to make this design with fewer inches of seam overall, but only by adding significantly to the complication and construction difficultly. Vertical seams are simple, easy to reinforce and if you eschew binding tape in favor of big seam allowances which can be folded and top stitched, pretty darn resistant. A bag this tall and skinny is a specialist tool for ultralight mountain backpackers and canyon hikers, and really not the most versatile design.
Larger bags, with suitable compression, are more open to compromise.
Problem 2: Lightweight fabrics which are durable enough for real world longevity.
I’ve written far too often and in many places that lightweight fabrics are not the most efficient way to make a light backpack, and with decently spare designs hardly ever having more than 2 yards once everything is added up (reinforcements, belt, harness, etc) this is true. But weight is still weight and pack fabrics remain one of the more common areas where fat could be rendered. This post has been one of my most read, ever, since I published it over three years ago, and while the specific options have expanded, the landscape has not much changed. And probably won’t until someone starts using woven dyneema in a way where they aren’t obliged to upcharge the hell out of it. (One wonders if HMG changed their whole 4400 line to woven what the net effect would be on price, over 3 years.) For my own use, the varieties of 210 denier D-P laminate remain the point where fabric is too light. I made the body of my fatbike framebag, usually a fairly low impact area, out of X21RC, and the damn thing has a little hole after less than a month. From what, I could not say. This is evidence of a divide which will always exist in the different types of durability different people demand; X21 does fine in all but the nastiest brush, but get it close to pointy rocks at it wilts like a rose hit with Fluroxypyr.
The pack pictured here is make mainly from a prototype fabric (the coyote tan stuff), which is a 330 denier Cordura with a very thick PET laminate. The company in question called me last spring and asked for my thoughts on the ideal pack fabric. In summary, my feedback was to make X33 without the X-ply, perhaps a thicker film, no backer, and in a nice lighter earth tone. They delivered, and M and I happily used packs made from it all last summer (seen in action here among other places). It remains the best pack fabric I’ve used. I now possess all of what remains from the test run, and am putting it to use very sparingly. Said company is looking for a party interested enough to invest in a larger production run, and if any reader fits that description, they should email me so I can set up a conversation that might put more of this stuff out into the world.
The reinforcement patches shown are plain PU coated 330 denier Cordura, in a lovely dark dark green that photos poorly put sets off the coyote nicely in natural light. Laminate fabrics (D-P and hybrid cuben, essentially) have many virtues when used in backpacks, but aren’t the holy grail. Truly good PU coatings come close when it comes to waterproofing, and hardly anyone is in a position to really comment on how the heavier laminate fabrics will stack up in terms of delamination. Probably not a pragmatic concern for many, but if light hybrid cuben can start to delam in under a year of heavy use, one has to assume the burly stuff will eventually. The nice thing for the moment is that the relative scarcity of laminate fabrics and their place as a premium product has kept quality high. Trying to source good PU Cordura in small batches is a roll of the dice, whereas one can buy X33 or X50 and know all aspects are top shelf.
The reason for the reinforcement patches on the base and sides of this pack are to experiment with how light a fabric will stand up to hard canyon use. I shredded a simple X51 bag in about 7 total hours of use doing this back in December, and the numerous were all exclusively due to harder things (rope, waterbottle, full drybag) pressing from the inside. Theses reinforcement patches are 1/4″ bigger than the main body panels, which will hopefully deflect pressure and allow the fabric to perform closer to its potential.
Problem 3: Enough suspension, but not too much.
At this point, any time I have a hipbelt on a backpack I want some form of rigidish (read, metal) suspension, well anchored. There are acute limits to just chucking a center stay in, but there are also very substantive benefits, and not that severe a weight penalty. I was genuinely shocked two weekends ago to see just how vague the connection between the stays and harness elements of the HMG 4400 packs are, testament I deem to how low the bar is in this department. The trick isn’t just to make a decently stiff without having to add too much weight in the form of supporting and connecting elements, it is to build the proper amount of play into that frame (which is probably why the HMG system is so beloved). There are plenty of options available for massive loads, and some decent ones for light loads, but it seems to me that the middle ground of 30-50 pounds still needs attention.
Carbon will remain problematic until a company can invest in proper molds and manufacturing which can produce a contoured product that won’t break. Stone Glacier and Zpacks have, in very different directions, taken straight carbon as far as it can go. That the former is adding 6 ounces to the stays alone just to achieve a modicum of curve should tell us something about the limitations of a straight frame.
For this pack, I put on thick shoulder straps, an external pad sleeve, and inside the sleeve loops to attach a webbing hipbelt. 90% of the time I won’t use a belt, but it is a good option, and a removable pad adds just the right amount of structure.
Problem 4: Closures
I have a profoundly mixed relationship with roll tops. On the one hand they’re clean, weatherproof, provide vertical compression without extra straps, and are the easiest closure to sew (one of the reasons they’re so popular). On the other, they’re fiddly and require buckles, which are the next enemy after seams, and a more intractable one. I tried a drawcord and top strap on this one, and am not sure I like it. In theory it’s faster and allows for overflow capacity, but I’m not sure that theory holds water any more. There is a large extent to which chasing “easy” closures and quick access ends up being a half-assed solution for organization on the part of the user.
Problem 5: Side pockets
Side pockets on packs are a horrid nuisance. Slapping on a flat panel of stretch fabric is the simplest solution, and one which actually works pretty well until they get shredded. Fabric pockets are tougher, and if abrasion against rocks is not much of a concern making them huge and putting them all the way against the bottom seam should guarantee good access and plenty of capacity. My problem is that I don’t always want side pockets. In canyons they get destroyed, and they interfere with the placement of compression straps, and the attachment of things such as skis. Is there a way to make them modular while not sucking? That is the next project.
Bedrock & Paradox 
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